REM BBC BASIC Integrated Development Environment for SDL 2.0 platforms
      REM Version 1.44a by Richard Russell, www.rtrussell.co.uk, 20-Mar-2026
      REM Copyright (C) R. T. Russell 2026
      
      REM!Embed @lib$+"dlglib", @lib$+"sortlib", @lib$+"stringlib", @lib$+"fnusing", @lib$+"script"
      REM!Embed @dir$+"SDLIDE.bmp", @dir$+"SDLIDEdark.bmp", @dir$+"profiler", @dir$+"listvars"
      REM!Embed @dir$+"crossref", @dir$+"searchin", @dir$+"memmon", @dir$+"macrorec", @dir$+"addconst"
      REM!Embed @dir$+"versinfo", @lib$+"utf8lib", @lib$+"sdlconsts.db"
      
      Ver$ = "1.44a"
      Year$ = "2026"
      Title$ = "SDLIDE version " + Ver$
      BB4W% = (INKEY(-256) == &57)
      *ESC OFF
      *SYS 4
      *KEY 2 #
      HIMEM = PAGE + &1000000
      
      REM!WC Windows and SDL constants:
      BS_BITMAP = &80
      CP_UTF8 = &FDE9
      ES_NUMBER = 8192
      IDCANCEL = 2
      IDNO = 7
      IDYES = 6
      MB_ICONWARNING = 48
      MB_ICONQUESTION = 32
      MB_ICONINFORMATION = 64
      MB_YESNO = 4
      MB_YESNOCANCEL = 3
      SS_RIGHT = 2
      SW_MAXIMIZE = 3
      WM_SIZE = 5
      SDL_MESSAGEBOX_ERROR = &10
      SDL_MESSAGEBOX_INFORMATION = &40
      WS_DISABLED = &8000000
      WS_TABSTOP = 65536
      WS_VSCROLL = &200000
      
      IF BB4W% THEN
        SYS "SetWindowText", @hwnd%, Title$
        SYS "QueryPerformanceCounter", ^N%%
        Session$ = STR$(N%% AND &7FFFFFF)
        GUIFont$ = "Segoe UI,10"
        EditFont$ = "Courier New,11,B"
        Platform$ = "BB4W"
        SYS "SetStretchBltMode", @memhdc%, 4
      ELSE
        SYS "SDL_SetWindowTitle", @hwnd%, Title$, @memhdc%
        SYS "SDL_GetPerformanceCounter" TO N%%
        Session$ = STR$(N%% AND &7FFFFFF)
        GUIFont$ = """"+@lib$+"DejaVuSans"",12"
        EditFont$ = """"+@lib$+"DejaVuSansMono"",11"
        CASE @platform% AND &F OF
          WHEN 0: Platform$ = "Win32"
          WHEN 1: Platform$ = "Linux"
          WHEN 2: Platform$ = "MacOS"
        ENDCASE
        IF @platform% AND &40 Platform$ += " (64-bit)" ELSE Platform$ += " (32-bit)"
        SYS "SDL_SetHint", "SDL_RENDER_SCALE_QUALITY", "linear"
      ENDIF
      
      ON ERROR LOCAL IF FALSE THEN
        OSCLI "DELETE """ + @tmp$ + "sdldebug.dat"""
        OSCLI "DELETE """ + @tmp$ + "memusage.dat"""
      ENDIF : RESTORE ERROR
      
      REM Hotspot IDs (must be >= NBUTTONS):
      IDMENU1 = 21
      IDMENU2 = 22
      IDMENU3 = 23
      IDMENU4 = 24
      IDMENU5 = 25
      IDMENU6 = 26
      IDSCRLD = 27
      IDPAGED = 28
      IDVSCRL = 29
      IDPAGEU = 30
      IDSCRLU = 31
      IDSCRLL = 32
      IDPAGEL = 33
      IDHSCRL = 34
      IDPAGER = 35
      IDSCRLR = 36
      IDCOMBO = 37
      IDPOPUP = 38
      
      REM Auto repeat delay (deciseconds):
      DELAY = 5
      
      REM Double-click time (centiseconds):
      DBLCLICK = 25
      
      REM Colour numbers:
      COL_GUITEXT = 0
      COL_KEYWD = 1
      COL_STRING = 2
      COL_DEF = 3
      COL_REMARK = 4
      COL_LABEL = 5
      COL_THEREST = 6
      COL_GUIBKGD = 7
      COL_BORDERS = 8
      COL_DISABLED = 9
      COL_PRESSED = 10
      COL_HILITEAND = 11
      COL_HILITEOR = 12
      COL_SELECT = 13
      COL_ICONS = 14
      COL_EDITPANE = 15
      
      REM Comparator constants:
      OP_INSERT = 1
      OP_DELETE = 2
      
      REM Process command line:
      Cmd$ = @cmd$ : C% = INSTR(Cmd$, "-hidden")
      IF C% THEN Cmd$ = LEFT$(Cmd$, C%-1) + MID$(Cmd$, C%+7)
      C% = INSTR(Cmd$, "SDLIDE.bbc")
      IF C% Cmd$ = MID$(Cmd$, C%+10) : C% = INSTR(Cmd$, " ") : IF C% Cmd$ = MID$(Cmd$, C%+1)
      dashR% = 0 : dashA% = 0 : dashM% = 0 : dashT% = 0 : dashC% = 0 : dashD% = 0 : dashP% = 0
      WHILE ASC(Cmd$)=&20 Cmd$ = MID$(Cmd$,2) : ENDWHILE
      WHILE ASC(Cmd$)=&2D
        CASE MID$(Cmd$,2,1) OF
          WHEN "r","R": dashR% = TRUE : Cmd$ = MID$(Cmd$,3)
          WHEN "a","A": dashA% = TRUE : Cmd$ = MID$(Cmd$,3)
          WHEN "m","M": dashM% = TRUE : Cmd$ = MID$(Cmd$,3)
          WHEN "t","T": dashT% = TRUE : Cmd$ = MID$(Cmd$,3)
          WHEN "c","C": dashC% = TRUE : Cmd$ = MID$(Cmd$,3)
          WHEN "d","D": dashD% = TRUE : Cmd$ = MID$(Cmd$,3)
          WHEN "p","P": dashP% = TRUE : Cmd$ = MID$(Cmd$,3)
          OTHERWISE: EXIT WHILE
        ENDCASE
        WHILE ASC(Cmd$)=&20 Cmd$ = MID$(Cmd$,2) : ENDWHILE
      ENDWHILE
      WHILE RIGHT$(Cmd$)=" " Cmd$ = LEFT$(Cmd$) : ENDWHILE
      IF ASC(Cmd$) = &22 Cmd$ = EVAL(Cmd$)
      
      REM Get INI file path:
      IniFile$ = @usr$ + "sdlide.ini"
      
      REM Load BBC BASIC libraries:
      INSTALL @lib$ + "fnusing"
      INSTALL @lib$ + "stringlib"
      INSTALL @lib$ + "sortlib"
      INSTALL @lib$ + "dlglib"
      INSTALL @lib$ + "script"
      INSTALL @lib$ + "utf8lib"
      Sort%% = FN_sortinit(0,2)
      
      REM Find address of string accumulator:
      IF NOT BB4W% IF @platform% AND &40 Accs%% = ]332 ELSE Accs%% = !332
      
      REM Get window size and position:
      WindowW% = VALFNgetINIstring(IniFile$, "windowwidth", "960")
      WindowH% = VALFNgetINIstring(IniFile$, "windowheight", "600")
      IsMaximized% = VALFNgetINIstring(IniFile$, "maximized", "0")
      
      REM Initialise window:
      VDU 23,22,WindowW%;WindowH%;8,16,16,128+8
      OFF
      IF IsMaximized% THEN
        IF BB4W% THEN
          SYS "ShowWindow", @hwnd%, SW_MAXIMIZE
        ELSE
          SYS "SDL_MaximizeWindow", @hwnd% : WAIT 10
        ENDIF
        VDU 26
      ENDIF
      
      REM Get remaining preferences:
      Overtype%    = FALSE
      Colouring%   = VALFNgetINIstring(IniFile$, "colouring", "-1")
      Indentation% = VALFNgetINIstring(IniFile$, "indentation", "-1")
      Lowercase%   = VALFNgetINIstring(IniFile$, "lowercase", "0")
      Abbrev%      = VALFNgetINIstring(IniFile$, "abbreviations", "0")
      Tooltips%    = VALFNgetINIstring(IniFile$, "tooltips", "1")
      Darkmode%    = VALFNgetINIstring(IniFile$, "darkmode", "0")
      Unicode%     = VALFNgetINIstring(IniFile$, "unicode", "-1")
      IncludeON%   = VALFNgetINIstring(IniFile$, "includeon", "-1")
      IncludeLab%  = VALFNgetINIstring(IniFile$, "includelab", "-1")
      SortList%    = VALFNgetINIstring(IniFile$, "sortlist", "-1")
      Hovertime%   = VALFNgetINIstring(IniFile$, "hovertime", "4")
      WheelSpeed   = VALFNgetINIstring(IniFile$, "wheelspeed", "1.0")
      GUIscale     = VALFNgetINIstring(IniFile$, "guiscale", "2.0")
      newGUIFont$  = FNgetINIstring(IniFile$, "guifont", GUIFont$)
      newEditFont$ = FNgetINIstring(IniFile$, "editfont", EditFont$)
      
      REM Check whether fonts are valid:
      ON ERROR LOCAL IF FALSE THEN
        OSCLI "FONT " + newGUIFont$
        GUIFont$ = newGUIFont$
      ENDIF : RESTORE ERROR
      ON ERROR LOCAL IF FALSE THEN
        OSCLI "FONT " + newEditFont$
        EditFont$ = newEditFont$
      ENDIF : RESTORE ERROR
      
      REM Window furniture metrics:
      BREAKPTBARWIDTH = 16 * GUIscale
      SCROLLBARSIZE  = 24 * GUIscale
      STATUSBARHEIGHT = 32 * GUIscale
      MINCOMBO = 150 * GUIscale
      GAPCOMBO = 50 * GUIscale
      
      REM Menu and toolbar metrics (must match SDLIDE.bmp image):
      NMENUS = 6
      NBUTTONS = 21
      BMPWIDTH = 690 * GUIscale
      BMPHEIGHT = 66 * GUIscale
      BUTTONWIDTH = 29 * GUIscale
      BUTTONHEIGHT = 29 * GUIscale
      MENUBARHEIGHT = 32 * GUIscale
      DIM MenuPos%(NMENUS), MenuKey&(NMENUS-1), ToolPos%(NBUTTONS), ToolTip$(NBUTTONS)
      DIM ToolCmd%(NBUTTONS-1), TBenable&(NBUTTONS-1), TBpressed&(NBUTTONS-1)
      TBenable&() = 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1
      MenuPos%() = 0, 40, 84, 154, 233, 278, 328
      MenuPos%() *= INT(GUIscale * 256) : MenuPos%() DIV= 256
      MenuKey&() = 68, 35, 54, 55, 52, 85
      ToolPos%() = 0, 31, 62, 93, 132, 163, 194, 225, 256, 295, 326, \
      \            365, 396, 435, 466, 497, 528, 559, 590, 621, 660, 691
      ToolPos%() *= INT(GUIscale * 256) : ToolPos%() DIV= 256
      ToolCmd%() = 310, 311, 312, 317, 320, 321, 322, 323, 324, 327, 329, \
      \            332, 333, 350, 351, 353, 354, 355, 356, 358, 369
      ToolTip$() = "New", "Load", "Save", "Print", "Undo", "Redo", "Cut", "Copy", "Paste", \
      \            "Find", "Replace", "Renumber", "Compile", "Run", "Debug", "Stop", \
      \            "Pause", "Step Into", "Step Over", "Immediate", "About", "List FNs/PROCs"
      
      REM Declare global structures:
      DIM EditRect{l%,t%,r%,b%}
      DIM ComboBox{l%,t%,r%,b%}
      DIM BrkPtBar{l%,t%,r%,b%}
      DIM ScrlBarH{l%,t%,r%,b%,min%,max%,pos%,page%,thumb{l%,r%},scale}
      DIM ScrlBarV{l%,t%,r%,b%,min%,max%,pos%,page%,thumb{t%,b%},scale}
      
      REM Global arrays:
      DIM KeyWd$(159), GoBack%(100), Click%(2), InKey&(63), Script$(20)
      DIM Buffer$(&FFFF), BreakPt&(&FFFF), Indent%(&FFFF)
      DIM BBCPtr%(&FFFF), BBCTok&(&FFFF), Script&(&FFFF)
      GoBack%() = TRUE
      
      KeyWd$() = "AND","DIV","EOR","MOD","OR","ERROR","LINE","OFF",   \
      \"STEP","SPC","TAB(","ELSE","THEN","   ","OPENIN","PTR","PAGE", \
      \"TIME","LOMEM","HIMEM","ABS","ACS","ADVAL","ASC","ASN","ATN",  \
      \"BGET","COS","COUNT","DEG","ERL","ERR","EVAL","EXP","EXT",     \
      \"FALSE","FN","GET","INKEY","INSTR(","INT","LEN","LN","LOG",    \
      \"NOT","OPENUP","OPENOUT","PI","POINT(","POS","RAD","RND",      \
      \"SGN","SIN","SQR","TAN","TO","TRUE","USR","VAL","VPOS","CHR$", \
      \"GET$","INKEY$","LEFT$(","MID$(","RIGHT$(","STR$","STRING$(",  \
      \"EOF","SUM","WHILE","CASE","WHEN","OF","ENDCASE","OTHERWISE",  \
      \"ENDIF","ENDWHILE","PTR","PAGE","TIME","LOMEM","HIMEM",        \
      \"SOUND","BPUT","CALL","CHAIN","CLEAR","CLOSE","CLG","CLS",     \
      \"DATA","DEF","DIM","DRAW","END","ENDPROC","ENVELOPE","FOR",    \
      \"GOSUB","GOTO","GCOL","IF","INPUT","LET","LOCAL","MODE","MOVE",\
      \"NEXT","ON","VDU","PLOT","PRINT","PROC","READ","REM","REPEAT", \
      \"REPORT","RESTORE","RETURN","RUN","STOP","COLOUR","TRACE",     \
      \"UNTIL","WIDTH","OSCLI","","CIRCLE","ELLIPSE","FILL","MOUSE",  \
      \"ORIGIN","QUIT","RECTANGLE","SWAP","SYS","TINT","WAIT",        \
      \"INSTALL","","PRIVATE","BY","EXIT"
      
      InKey&() = 16, 66,101, 83, 51, 35, 68, 84, 85, 38, 70, 71, 87,102, 86, 55, \
      \          56, 17, 52, 82, 36, 54,100, 34, 67, 69, 98, 16, 16, 16, 16, 16, \
      \          99, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, \
      \          40, 49, 50, 18, 19, 20, 53, 37, 22, 39, 16, 16, 16, 16, 16, 16
      Left$ = ":"+CHR$&85+CHR$&8B+CHR$&8C+CHR$&D9+CHR$&EC+CHR$&F5+CHR$4+CHR$9
      Skip$ = ":"+CHR$214+CHR$220+CHR$228+CHR$229+CHR$231+CHR$238+CHR$243+CHR$244+"*\"
      Valid$ = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
      
      REM Set up right-to-left and complex scripts:
      Script$() = "Latn", "Deva", "Beng", "Guru", "Gujr", "Orya", "Taml", "Telu", "Knda", "Mlym", \
      \   "Thai", "Laoo", "Tibt", "Mymr", "Hang", "Khmr", "Hebr", "Arab", "Syrc", "Nkoo", "Mong"
      
      Script&() = &FF : Script&(&22) = 0 : REM To quote RTL text correctly
      FOR I% = &0041 TO &005A : Script&(I%) = 0  : NEXT : REM Latin
      FOR I% = &0061 TO &007A : Script&(I%) = 0  : NEXT : REM Latin
      
      FOR I% = &0900 TO &097F : Script&(I%) = 1  : NEXT : REM Devanagari (Hindi)
      FOR I% = &0980 TO &09FF : Script&(I%) = 2  : NEXT : REM Bengali
      FOR I% = &0A00 TO &0A7F : Script&(I%) = 3  : NEXT : REM Gurmukhi (Punjabi)
      FOR I% = &0A80 TO &0AFF : Script&(I%) = 4  : NEXT : REM Gujarati
      FOR I% = &0B00 TO &0B7F : Script&(I%) = 5  : NEXT : REM Oriya
      FOR I% = &0B80 TO &0BFF : Script&(I%) = 6  : NEXT : REM Tamil
      FOR I% = &0C00 TO &0C7F : Script&(I%) = 7  : NEXT : REM Telugu
      FOR I% = &0C80 TO &0CFF : Script&(I%) = 8  : NEXT : REM Kannada
      FOR I% = &0D00 TO &0D7F : Script&(I%) = 9  : NEXT : REM Malayalam
      
      FOR I% = &0E00 TO &0E7F : Script&(I%) = 10 : NEXT : REM Thai
      FOR I% = &0E80 TO &0EFF : Script&(I%) = 11 : NEXT : REM Lao
      FOR I% = &0F00 TO &0FFF : Script&(I%) = 12 : NEXT : REM Tibetan
      FOR I% = &1000 TO &109F : Script&(I%) = 13 : NEXT : REM Myanmar
      FOR I% = &1100 TO &11FF : Script&(I%) = 14 : NEXT : REM Hangul (Korea)
      FOR I% = &1780 TO &17FF : Script&(I%) = 15 : NEXT : REM Khmer (Cambodia)
      FOR I% = &19E0 TO &19FF : Script&(I%) = 15 : NEXT : REM Khmer (Cambodia)
      
      FOR I% = &0590 TO &05FF : Script&(I%) = 16 : NEXT : REM Hebrew (RTL)
      FOR I% = &0600 TO &06FF : Script&(I%) = 17 : NEXT : REM Arabic (RTL)
      FOR I% = &0750 TO &077F : Script&(I%) = 17 : NEXT : REM Arabic (RTL)
      FOR I% = &0700 TO &074F : Script&(I%) = 18 : NEXT : REM Syriac (RTL)
      FOR I% = &07C0 TO &07FF : Script&(I%) = 19 : NEXT : REM N'Ko (RTL)
      FOR I% = &1800 TO &18AF : Script&(I%) = 20 : NEXT : REM Mongolian (RTL)
      
      REM Get recent files list:
      DIM Recent$(9)
      FOR i% = 1 TO 9
        Recent$(i%) = FNgetINIstring(IniFile$, "recent" + STR$(i%), "")
      NEXT
      
      REM Get addins list:
      DIM Addin$(9)
      FOR i% = 1 TO 9
        READ addin$
        IF addin$ <> "" addin$ = @dir$ + addin$ + ".bbc"
        Addin$(i%) = FNgetINIstring(IniFile$, "addin" + STR$(i%), addin$)
      NEXT
      DATA "crossref", "searchin", "memmon", "macrorec", "addconst", "versinfo", "", "", ""
      
      REM Get tooltip strings from the 'keywords.txt' file:
      DIM KeywTip$(255)
      F% = OPENIN(@lib$ + "../examples/keywords.txt")
      IF F% THEN
        INPUT #F%,tip$ : INPUT #F%,tip$
        FOR I% = 0 TO DIM(KeywTip$(),1)
          INPUT #F%, tip$ : IF ASCtip$ = &A tip$ = MID$(tip$, 2)
          KeywTip$(I%) = tip$
        NEXT I%
        CLOSE #F%
      ENDIF
      
      REM Get function key macros:
      FOR i% = 1 TO 11
        macro$ = FNgetINIstring(IniFile$, "macro" + STR$(i%), "")
        IF macro$ <> "" THEN OSCLI "KEY " + STR$i% + " " + macro$
      NEXT
      
      REM Get Acorn token replacement list:
      DIM Acorn&(15)
      FOR i% = 0 TO 15 : READ Acorn&(i%) : NEXT
      DATA &C8,&01,&03,&05,&F0,&07,&08,&C7,&0B,&04,&06,&09,&0C,&0C,&0A,&02
      
      REM Set colour palette:
      DIM Colours%(5)
      PROCsetpalette
      
      REM Create file and folder icons (must set font first):
      OSCLI "FONT " + GUIFont$
      
      C% = (1.5 * @vdu%!220 + 7) AND -8
      VDU 21
      OSCLI "spool """ + @tmp$ + "bbfile.vdu"""
      GCOL 14+128
      PLOT 0,C%,0 : PLOT 99,C%*0.75,-C%*0.75 : PLOT 0,C%/4,C%/4 : PLOT 0,-C%*0.75,0
      PLOT 115,-C%/2,-C%/2 : PLOT 0,C%/4,C%/4 : PLOT 98,C%*0.75,C%*0.75 : PLOT 0,0,-C%/2
      PLOT 1,C%/4,0 : PLOT 1,-C%/2,-C%/2 : PLOT 1,-C%*0.75,0 : PLOT 1,C%/4,C%/4
      PLOT 0,C%*1.25,C%*0.75 : PLOT 0,0,0
      OSCLI "spool """ + @tmp$ + "folder.vdu"""
      GCOL 14+128
      PLOT 0,C%,0 : PLOT 0,C%*0.75,0 : PLOT 99,-C%*0.75,-C%
      PLOT 0,C%/2,-C%/4 : PLOT 0,0,C% : PLOT 115,-C%/2,C%/4
      PLOT 1,0,-C% : PLOT 1,C%/2,-C%/4 : PLOT 1,0,C% : PLOT 1,-C%/2,C%/4
      PLOT 1,C%*0.75,0 : PLOT 1,0,-C% : PLOT 1,-C%*0.25,0 : PLOT 0,C%*0.75,C%
      *spool
      VDU 6
      F% = OPENIN(@tmp$ + "bbfile.vdu")
      BBfile$ = GET$#F% BY EXT#F%
      CLOSE #F%
      F% = OPENIN(@tmp$ + "folder.vdu")
      Folder$ = GET$#F% BY EXT#F%
      CLOSE #F%
      IF LEN(BBfile$) <> LEN(Folder$) ERROR 100, "Icons not equal size"
      
      REM Set up dialogue box templates:
      FileDlg% = FN_newdialog("Load File", 200, 200)
      PROC_textbox(FileDlg%, "", 104, 40, 169, 155, 10, 0)
      PROC_radiobutton(FileDlg%, "Tokenised", 106, 4, 185, 50, 11, 0)
      PROC_radiobutton(FileDlg%, "Text file", 107, 57, 185, 50, 11, 0)
      PROC_static(FileDlg%, "Folder:", 101, 3, 5, 35, 10, SS_RIGHT)
      PROC_static(FileDlg%, "File name:", 103, 3, 170, 35, 10, SS_RIGHT)
      PROC_radiobutton(FileDlg%, "BASIC programs", 108, 4, 185, 68, 11, 0) : REM Not contiguous
      PROC_radiobutton(FileDlg%, "All files", 109, 72, 185, 38, 11, 0)
      PROC_button(FileDlg%, "Open", 1, 110, 184, 40, 11, WS_DISABLED)
      PROC_button(FileDlg%, "Cancel", 2, 155, 184, 40, 11, 0)
      PROC_textbox(FileDlg%, "", 102, 40, 4, 155, 10, 0)
      IDlistbox% = FN_setproc(PROClistclick())
      PROC_listbox(FileDlg%, "", IDlistbox%, 5, 18, 190, 146, WS_VSCROLL)
      
      RenumDlg% = FN_newdialog("Renumber", 128, 76)
      PROC_static(RenumDlg%, "First line:", 101, 10, 9, 50, 10, SS_RIGHT)
      PROC_static(RenumDlg%, "Increment:", 102, 10, 25, 50, 10, SS_RIGHT)
      PROC_textbox(RenumDlg%, "10", 103, 66, 8, 28, 10, ES_NUMBER)
      PROC_textbox(RenumDlg%, "10", 104, 66, 24, 28, 10, ES_NUMBER)
      PROC_checkbox(RenumDlg%, "Remove unused line numbers", 105, 8, 42, 120, 12, 0)
      PROC_button(RenumDlg%, "OK", 1, 19, 58, 40, 11, 0)
      PROC_button(RenumDlg%, "Cancel", 2, 69, 58, 40, 11, 0)
      
      FindDlg% = FN_newdialog("Find", 200, 40)
      PROC_static(FindDlg%, "Find what:", 101, 3, 8, 44, 10, SS_RIGHT)
      PROC_textbox(FindDlg%, "", 103, 50, 6, 96, 10, 0)
      PROC_checkbox(FindDlg%, "Match whole word only", 105, 4, 26, 90, 12, 0)
      PROC_checkbox(FindDlg%, "Match case", 106, 98, 26, 52, 12, 0)
      PROC_button(FindDlg%, "Find Next", 1, 152, 6, 42, 11, WS_DISABLED)
      PROC_button(FindDlg%, "Cancel", 2, 152, 23, 42, 11, 0)
      
      ReplDlg% = FN_newdialog("Replace", 200, 74)
      PROC_static(ReplDlg%, "Find what:", 101, 3, 8, 46, 10, SS_RIGHT)
      PROC_static(ReplDlg%, "Replace with:", 102, 3, 25, 46, 10, SS_RIGHT)
      PROC_textbox(ReplDlg%, "", 103, 52, 6, 94, 10, 0)
      PROC_textbox(ReplDlg%, "", 104, 52, 23, 94, 10, 0)
      PROC_checkbox(ReplDlg%, "Match whole word only", 105, 4, 43, 90, 12, 0)
      PROC_checkbox(ReplDlg%, "Match case", 106, 4, 60, 52, 12, 0)
      PROC_button(ReplDlg%, "Find Next", 1, 152, 6, 42, 11, WS_DISABLED)
      PROC_button(ReplDlg%, "Replace", 3, 152, 23, 42, 11, WS_DISABLED)
      PROC_button(ReplDlg%, "Replace All", 4, 152, 40, 42, 11, WS_DISABLED)
      PROC_button(ReplDlg%, "Cancel", 2, 152, 57, 42, 11, 0)
      
      FontDlg% = FN_newdialog("Set Font", 230, 84)
      PROC_static(FontDlg%, "Typeface:", 100, 4, 4, 50, 9, 0)
      PROC_listbox(FontDlg%, "", 101, 4, 14, 96, 64, WS_VSCROLL)
      PROC_static(FontDlg%, "Style:", 102, 104, 4, 40, 9, 0)
      PROC_listbox(FontDlg%, "", 103, 104, 14, 40, 64, 0)
      PROC_static(FontDlg%, "Size:", 104, 148, 4, 30, 9, 0)
      PROC_listbox(FontDlg%, "", 105, 148, 14, 32, 64, WS_VSCROLL)
      PROC_button(FontDlg%, "OK", 1, 185, 14, 40, 11, 0)
      PROC_button(FontDlg%, "Cancel", 2, 185, 30, 40, 11, 0)
      PROC_button(FontDlg%, "Apply", 3, 185, 46, 40, 11, 0)
      
      ColorDlg% = FN_newdialog("Set Colours", 119, 154)
      PROC_static(ColorDlg%, "Basic colours:", 100, 4, 4, 50, 9, 0)
      PROC_groupbox(ColorDlg%, "Syntax colouring", 100, 4, 86, 110, 48, 0)
      PROC_radiobutton(ColorDlg%, "Line numbers", 105, 6, 95, 57, 11, 0)
      PROC_radiobutton(ColorDlg%, "DEFinitions", 103, 64, 95, 49, 11, 0)
      PROC_radiobutton(ColorDlg%, "Keywords", 101, 6, 108, 57, 11, 0)
      PROC_radiobutton(ColorDlg%, "REMarks", 104, 64, 108, 49, 11, 0)
      PROC_radiobutton(ColorDlg%, "Strings", 102, 6, 121, 57, 11, 0)
      PROC_radiobutton(ColorDlg%, "The rest", 106, 64, 121, 49, 11, 0)
      PROC_button(ColorDlg%, "OK", 1, 4, 139, 34, 11, 0)
      PROC_button(ColorDlg%, "Apply", 3, 42, 139, 34, 11, 0)
      PROC_button(ColorDlg%, "Cancel", 2, 80, 139, 34, 11, 0)
      
      GotoDlg% = FN_newdialog("Go To Line", 120, 50)
      PROC_static(GotoDlg%, "Line number:", 100, 4, 4, 50, 9, 0)
      PROC_textbox(GotoDlg%, "0", 101, 4, 14, 111, 9, ES_NUMBER)
      PROC_button(GotoDlg%, "Go To", 1, 41, 30, 34, 11, 0)
      PROC_button(GotoDlg%, "Cancel", 2, 80, 30, 34, 11, 0)
      
      AboutBox% = FN_newdialog("About SDLIDE", 150, 72)
      PROC_static(AboutBox%, "BBC BASIC for SDL 2.0", 101, 4,  4, 142, 9, SS_CENTER)
      PROC_static(AboutBox%, "Integrated Development Environment", 102, 4, 14, 142, 9, SS_CENTER)
      PROC_static(AboutBox%, Platform$ + " Version " + Ver$, 103, 4, 24, 142, 9, SS_CENTER)
      PROC_static(AboutBox%, "Copyright © R. T. Russell " + Year$, 104, 4, 34, 142, 9, SS_CENTER)
      PROC_static(AboutBox%, "http://www.rtrussell.co.uk/", 105, 4, 44, 142, 9, SS_CENTER)
      PROC_button(AboutBox%, "OK", 1, 58, 56, 34, 11, 0)
      
      OSCLI "FONT " + EditFont$
      Compare% = FN_newdialog("", 0, 0)
      PROC_listbox(Compare%, "", 400, BREAKPTBARWIDTH, \
      \          BMPHEIGHT, 2 * @vdu%!208 - BREAKPTBARWIDTH, \
      \          2*@vdu%!212 - STATUSBARHEIGHT - BMPHEIGHT, \
      \          WS_VSCROLL)
      
      REM Create a 48-colour palette for the Set Colours dialogue:
      IF BB4W% SYS "GetPaletteEntries", @hpal%, 0, 1, ^savpal% ELSE savpal% = !@hpal%
      DIM Palette%(5,7), gamma4&(3), gamma3&(2)
      gamma4&() = &00, &80, &C0, &FF : gamma3&() = &00, &C0, &FF
      FOR row% = 5 TO 0 STEP -1
        FOR col% = 7 TO 0 STEP -1
          r& = gamma4&(col% MOD 4)
          g& = gamma4&((row% DIV 3) * 2 + col% DIV 4)
          b& = gamma3&(row% MOD 3)
          Palette%(row%, col%) = (r& << 16) OR (g& << 8) OR b&
          COLOR 0, r&, g&, b&
          GCOL 0 : RECTANGLE FILL 0, 0, 32, 32
          bmp$ = @tmp$ + "cc" + Session$ + STR$row% + STR$col% + ".tmp.bmp"
          OSCLI "gsave """ + bmp$ + """ 0, 0, 32, 32"
          PROC_button(ColorDlg%, bmp$, 200 + row% * 10 + col%, 4 + col% * 14, \
          \           14 + row% * 12, 12, 10, WS_TABSTOP OR BS_BITMAP)
        NEXT
      NEXT row%
      IF BB4W% SYS "SetPaletteEntries", @hpal%, 0, 1, ^savpal% ELSE !@hpal% = savpal%
      
      REM Set up menus:
      DIM FileMenu$(21), FileMenu%(21)
      FileMenu%() = 310,311,&1000+312,313,0,314,315,0,&1000+316, \
      \             317,0,381,382,383,384,385,386,387,388,389,0,319
      FileMenu$() = "&New"+CHR$9+"Ctrl+N", \
      \             "&Load..."+CHR$9+"Ctrl+L", \
      \             "&Save"+CHR$9+"Ctrl+S", \
      \             "Save &As...", \
      \             "", \
      \             "&Insert..."+CHR$9+"Ctrl+I", \
      \             "&Compare...", \
      \             "", \
      \             "Page Se&tup...", \
      \             "&Print..."+CHR$9+"Ctrl+P"
      FOR i% = 1 TO 9
        FileMenu$(i%+10) = "&" + STR$(i%) + " " + FNnopath(Recent$(i%))
      NEXT
      FileMenu$(21) = "E&xit"
      
      DIM EditMenu$(13), EditMenu%(13)
      EditMenu%() = &1000+320,&1000+321,0,&1000+322,&1000+323,&1000+324,&1000+325, \
      \             0,326,0,327,328,329,331
      EditMenu$() = "&Undo"+CHR$9+"Ctrl+Z", \
      \           "&Redo"+CHR$9+"Ctrl+Y", \
      \           "", \
      \           "Cu&t"+CHR$9+"Ctrl+X", \
      \           "&Copy"+CHR$9+"Ctrl+C", \
      \           "&Paste"+CHR$9+"Ctrl+V", \
      \           "De&lete"+CHR$9+"Del", \
      \           "", \
      \           "Select &All"+CHR$9+"Ctrl+A", \
      \           "", \
      \           "&Find..."+CHR$9+"Ctrl+F", \
      \           "Find &Next"+CHR$9+"F3", \
      \           "R&eplace..."+CHR$9+"Ctrl+R", \
      \           "&Go To..."+CHR$9+"Ctrl+G"
      
      DIM UtilMenu$(16), UtilMenu%(16)
      UtilMenu%() = &1000+332,&1000+333,0,&1000+334,335,336,337
      UtilMenu$() = "&Renumber...", \
      \           "&Compile...", \
      \           "", \
      \           "&List FNs/PROCs", \
      \           "Include &ONs", \
      \           "&Include Labels", \
      \           "&Sort List"
      FOR i% = 1 TO 9
        UtilMenu$(i%+7) = "&" + STR$(i%) + " " + FNnopath(Addin$(i%))
        UtilMenu%(i%+7) = 390 + i%
        IF Addin$(i%) = "" UtilMenu%(i%+7) += &1000
      NEXT
      
      DIM OptsMenu$(9), OptsMenu%(9)
      OptsMenu%() = 340,341,342,343,318,0,346,347,348,349
      OptsMenu$() = "Synta&x Colouring", \
      \           "&Lowercase Keywords", \
      \           "&Indentation", \
      \           "&Unicode", \
      \           "&Abbreviations", \
      \           "", \
      \           "Set &Font...", \
      \           "Set &Colours...", \
      \           "&Hover Tooltips", \
      \           "&Dark Mode"
      
      DIM RunMenu$(11), RunMenu%(11)
      RunMenu%() = 350,351,352,&1000+353,&1000+354,&1000+355,&1000+356,357,358,0,344,345
      RunMenu$() = "&Run Program"+CHR$9+"F9", \
      \           "&Debug Program", \
      \           "Pro&file Program", \
      \           "&Stop", \
      \           "&Pause"+CHR$9+"F8", \
      \           "St&ep Into"+CHR$9+"F7", \
      \           "Step &Over"+CHR$9+"F5", \
      \           "Run &To Cursor"+CHR$9+"F6", \
      \           "&Immediate Mode", \
      \           "", \
      \           "Toggle &Breakpoint"+CHR$9+"Ctrl+B", \
      \           "&Clear Breakpoints"+CHR$9+"F4"
      
      DIM HelpMenu$(8), HelpMenu%(8)
      HelpMenu%() = 360,361,362,363,364,365,366,0,369
      HelpMenu$() = "&Help Topics"+CHR$9+"F1", \
      \           "&Tutorial", \
      \           "&Email", \
      \           "&Website", \
      \           "&Discussion group", \
      \           "&Forum", \
      \           "Wi&ki", \
      \           "", \
      \           "&About SDLIDE..."
      
      DIM BkPtMenu$(1), BkPtMenu%(1) : BkPtMenu%() = 1
      BkPtMenu$() = "&Toggle breakpoint", \
      \           "&Clear all breakpoints"
      
      REM Menu help messages:
      DIM MenuHelp$(379)
      MenuHelp$() = "", "New, load, save, print or exit", \
      \             "Cut, copy, paste, delete, search or replace", \
      \             "Renumber, compile or list FNs and PROCs", \
      \             "Program options and customisation", \
      \             "Run, stop or debug the BBC BASIC program", \
      \             "Help information"
      
      MenuHelp$(310) = "Start a new BBC BASIC program"
      MenuHelp$(311) = "Load an existing BBC BASIC program"
      MenuHelp$(312) = "Save the current BBC BASIC program"
      MenuHelp$(313) = "Save the current program with a new name or in a different format"
      MenuHelp$(314) = "Insert a file before the current line"
      MenuHelp$(315) = "Show the differences from an earlier version of the program"
      MenuHelp$(316) = "Select paper size, orientation, margins etc."
      MenuHelp$(317) = "Print the current program"
      MenuHelp$(319) = "Exit SDLIDE"
      
      MenuHelp$(320) = "Undo the effect of the last editing operation"
      MenuHelp$(321) = "Reverse the effect of the last undo"
      MenuHelp$(322) = "Cut the selection and put it on the Clipboard"
      MenuHelp$(323) = "Copy the selection and put it on the Clipboard"
      MenuHelp$(324) = "Insert the Clipboard contents at the current point"
      MenuHelp$(325) = "Delete the selection"
      MenuHelp$(326) = "Select the entire program"
      MenuHelp$(327) = "Search the current program"
      MenuHelp$(328) = "Search for the next occurrence"
      MenuHelp$(329) = "Search for and replace a string"
      MenuHelp$(331) = "Move the cursor to the specified line (zero based)"
      
      MenuHelp$(332) = "Renumber the current program"
      MenuHelp$(333) = "Create a stand-alone application"
      MenuHelp$(334) = "List the program's functions and procedures"
      MenuHelp$(335) = "Include ON events in the FN/PROC list"
      MenuHelp$(336) = "Include labels in the FN/PROC list"
      MenuHelp$(337) = "Sort the list of functions and procedures"
      
      MenuHelp$(340) = "Highlight language elements in colour"
      MenuHelp$(341) = "Display and accept keywords in lower case"
      MenuHelp$(342) = "Enable or disable automatic indentation"
      MenuHelp$(343) = "Show literal strings as Unicode rather than ANSI"
      MenuHelp$(318) = "Accept keyword abbreviations"
      MenuHelp$(346) = "Select the screen font and size"
      MenuHelp$(347) = "Select the colours used for highlighting"
      MenuHelp$(348) = "Enable or disable tooltips when hovering"
      MenuHelp$(349) = "Enable or disable the dark colour scheme"
      
      MenuHelp$(350) = "Run the current program"
      MenuHelp$(351) = "Run the current program with debugging aids"
      MenuHelp$(352) = "Run the current program and generate a profiler report"
      MenuHelp$(353) = "Stop and quit the current program"
      MenuHelp$(354) = "Pause execution of the current program"
      MenuHelp$(355) = "Execute a single program statement"
      MenuHelp$(356) = "Execute statements and pause on the next line"
      MenuHelp$(357) = "Run and pause at the line containing the cursor"
      MenuHelp$(358) = "Enter commands for immediate execution"
      MenuHelp$(344) = "Set or clear a breakpoint on the current line"
      MenuHelp$(345) = "Clear all breakpoints"
      
      MenuHelp$(360) = "Find help for BBC BASIC"
      MenuHelp$(361) = "Open the BBC BASIC beginners' tutorial"
      MenuHelp$(362) = "Request help by email"
      MenuHelp$(363) = "Visit the BBC BASIC website"
      MenuHelp$(364) = "Get help and advice at the BBC BASIC discussion group"
      MenuHelp$(365) = "Discuss BBC BASIC at the forum"
      MenuHelp$(366) = "Find programming tips on the BBC BASIC Wiki"
      MenuHelp$(369) = "About this program"
      
      MenuHelp$(370) = "Add a REM to every selected line"
      MenuHelp$(371) = "Remove the REMs from the selected lines"
      MenuHelp$(372) = "Jump back to the place you last came from"
      MenuHelp$(373) = "Jump to the specified function or procedure"
      
      REM Initialise global variables:
      CurrentFile$ = ""
      Unsaved% = FALSE
      nLines% = 0
      MaxLen% = 0
      ScrollH% = 0
      ScrollV% = 0
      CaretX% = 0
      CaretY% = 0
      AnchorX% = 0
      AnchorY% = 0
      SelCol% = 0
      Hover% = -10000
      
      REM Handle command-line options (before ON ERROR):
      IF Cmd$<>"" PROCload(Cmd$, nLines%, MaxLen%, FALSE)
      IF dashC% PROCcompile
      IF dashR% PROCrun
      IF dashD% PROCdebug
      IF dashP% PROCprofile
      IF dashA% PROCcleanup : QUIT
      
      Changed% = FALSE
      Resized% = FALSE
      Refresh% = TRUE
      Pressed% = 0
      UndoLevel% = 0
      RedoLevel% = 0
      BackLevel% = 0
      FindFlags% = 0
      Dragging% = 0
      Repeating% = FALSE
      KeepSelection% = FALSE
      RepTimer% = 0
      StaTimer% = 0
      Typing% = FALSE
      oldCaretX% = -1
      oldCaretY% = -1
      oldAnchorX% = -1
      oldAnchorY% = -1
      oldScrollH% = -1
      oldScrollV% = -1
      ScrollTime% = 0
      DblClkTime% = 0
      SelWord$ = ""
      
      PROCdrawall(@vdu%!208, @vdu%!212)
      
      REM Set event interrupts:
      *TIMER 100
      ON CLOSE IF @lparam%=0 IF FNoktoditch IF FNexit PROCcleanup : QUIT ELSE RETURN
      ON ERROR ON ERROR OFF PROCerror(ERR, REPORT$) : PROCcleanup : QUIT
      ON MOVE PROCmove(@msg%, @wparam%, @lparam%) : RETURN
      ON TIME PROCtimer(FALSE) : RETURN
      ON MOUSE PROCmouse(@wparam%, @lparam%) : RETURN
      ON SYS PROCscroll(@lparam%) : RETURN
      
      REM Main polling loop:
      DIM click%(2)
      Click%(0) = TRUE
      minx% = 0
      maxy% = 0
      REPEAT
        charx% = 2 * @vdu%!216
        chary% = 2 * @vdu%!220
        maxx% = EditRect.r% - EditRect.l%
        miny% = EditRect.b% - EditRect.t% + chary%
        rows% = (maxy% - miny%) DIV chary%
        
        click%(0) = TRUE
        SWAP click%(),Click%()
        IF click%(0)=TRUE click%(0) = INKEY(0)
        
        IF click%(0) = TRUE THEN
          StaTimer% += 1
          IF StaTimer% >= 10 THEN
            StaTimer% = 0
            PROCdrawstatusbar(0, TRUE, FALSE)
          ENDIF
        ELSE
          Hover% = -10000 : REM Don't popup tooltip
          F% = FALSE : REM Don't flush keyboard buffer
          T% = FALSE : REM Cancel 'currently typing'
          CASE click%(0) OF
              
            WHEN 128: PROCwordleft
            WHEN 129: PROCwordright
            WHEN 130: CaretX% = 0
            WHEN 131: I% = Indent%(CaretY%) : CaretX% = FNlen(FNformat(Buffer$(CaretY%), I%))
            WHEN 132: ScrollV% -= rows% * chary% : CaretY% -= rows% : F% = TRUE : T% = TRUE
            WHEN 133: ScrollV% += rows% * chary% : CaretY% += rows% : F% = TRUE : T% = TRUE
            WHEN 158: ScrollH% += maxx% - minx% : F% = TRUE : T% = TRUE
            WHEN 159: ScrollH% -= maxx% - minx% : F% = TRUE : T% = TRUE
            WHEN 136: IF INKEY(-3) PROCwordleft ELSE IF CaretX% CaretX% -= 1 : F% = TRUE
            WHEN 137: IF INKEY(-3) PROCwordright ELSE CaretX% += 1 : F% = TRUE
            WHEN 138: IF CaretY% < nLines% CaretY% += 1 : F% = TRUE
            WHEN 139: IF CaretY% CaretY% -= 1 : F% = TRUE
            WHEN 140: REPEAT ScrollV% += chary% * WheelSpeed : UNTIL INKEY(0) <> 140 : T% = TRUE
            WHEN 141: REPEAT ScrollV% -= chary% * WheelSpeed : UNTIL INKEY(0) <> 141 : T% = TRUE
            WHEN 142: ScrollH% -= charx% : T% = TRUE
            WHEN 143: ScrollH% += charx% : T% = TRUE
            WHEN 146: REPEAT ScrollV% += chary% : UNTIL INKEY(0) <> 146 : T% = TRUE
            WHEN 144: REPEAT ScrollV% -= chary% : UNTIL INKEY(0) <> 144 : T% = TRUE
            WHEN 156: CaretX% = 0 : CaretY% = 0
            WHEN 157: CaretX% = 0 : CaretY% = nLines%
              
            WHEN 134: Overtype% = NOT Overtype%  : T% = TRUE
            WHEN 135:   PROCdelete(INKEY(-2) OR INKEY(-3))    : Changed% = TRUE : F% = TRUE : T% = TRUE
            WHEN 8,127: PROCbackspace(INKEY(-2) OR INKEY(-3)) : Changed% = TRUE : F% = TRUE : T% = TRUE
            WHEN 13:    PROCreturn                            : Changed% = TRUE : F% = TRUE : T% = TRUE
              
            WHEN 310,14: IF FNoktoditch PROCnew
            WHEN 311,12: IF FNoktoditch PROCload
            WHEN 312,19: IF FNsave PROCunchanged
            WHEN 313: IF FNsaveas PROCunchanged
            WHEN 314,9:
              IF INKEY(-2) OR click%(0) = 314 THEN
                PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
                IF FNinsertfile Changed% = TRUE
              ELSE
                PROCputkey(155)
              ENDIF
            WHEN 315: PROCcomparefile
            WHEN 317,16: PROCprintprogram
            WHEN 319: IF FNoktoditch IF FNexit PROCcleanup : QUIT
              
            WHEN 26,320: REM Undo
              IF UndoLevel% THEN
                IF RedoLevel% = 0 THEN
                  PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
                  UndoLevel% -= 1 : RedoLevel% = UndoLevel%
                ENDIF
                UndoLevel% -= 1
                PROCundoundo(Buffer$(), Indent%(), BreakPt&(), nLines%, UndoLevel%, CaretX%, CaretY%)
                Changed% = TRUE
              ENDIF
            WHEN 25,321: REM Redo
              IF RedoLevel% > UndoLevel% THEN
                UndoLevel% += 1
                PROCundoundo(Buffer$(), Indent%(), BreakPt&(), nLines%, UndoLevel%, CaretX%, CaretY%)
                Changed% = TRUE
              ENDIF
            WHEN 24,322: REM Cut
              IF CaretX% <> AnchorX% OR CaretY% <> AnchorY% THEN
                PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
                PROCcopytext(Buffer$(), Indent%(), CaretX%, CaretY%, AnchorX%, AnchorY%)
                PROCdeltext(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
                Changed% = TRUE
              ENDIF
            WHEN 3,323: REM Copy
              IF CaretX% <> AnchorX% OR CaretY% <> AnchorY% THEN
                PROCcopytext(Buffer$(), Indent%(), CaretX%, CaretY%, AnchorX%, AnchorY%)
              ENDIF
            WHEN 22,324: REM Paste
              IF FNhascliptext THEN
                PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
                PROCdeltext(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
                PROCpaste(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, nLines%, MaxLen%)
                Changed% = TRUE
              ENDIF
            WHEN 325: REM Delete
              IF CaretX% <> AnchorX% OR CaretY% <> AnchorY% THEN
                PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
                PROCdeltext(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
                Changed% = TRUE
              ENDIF
            WHEN 1,326: REM Select All
              AnchorX% = 0 : AnchorY% = 0
              CaretX% = 0 : CaretY% = nLines%
              KeepSelection% = TRUE
              Refresh% = TRUE
            WHEN 6,327: PROCfind       : KeepSelection% = TRUE
            WHEN 147,328: PROCfindnext : KeepSelection% = TRUE
            WHEN 18,329: PROCreplace   : KeepSelection% = TRUE
            WHEN 7,331: PROCgotoline(nLines%)
              
            WHEN 332: PROCrenumber(Buffer$(), nLines%)
            WHEN 333: PROCcompile
            WHEN 334: PROClistdefs(Buffer$(), nLines%)
            WHEN 335: IncludeON% EOR= TRUE
            WHEN 336: IncludeLab% EOR= TRUE
            WHEN 337: SortList% EOR= TRUE
              
            WHEN 340: PROCtogglecolouring
            WHEN 341: PROCtogglelowercase
            WHEN 342: PROCtoggleindentation
            WHEN 343: PROCtoggleunicode
            WHEN 318: PROCtoggleabbrev
            WHEN 346: PROCsetfont
            WHEN 347: PROCsetcolours
            WHEN 348: Tooltips% EOR= TRUE
            WHEN 349: PROCtoggledarkmode
              
            WHEN 153,350: PROCrun
            WHEN 351: PROCdebug
            WHEN 352: PROCprofile
            WHEN 353: PROCstop
            WHEN 152,354: PROCpause
            WHEN 151,355: PROCstepinto
            WHEN 149,356: PROCstepover
            WHEN 150,357: PROCrununtil
            WHEN 358: PROCimmediate : ON
            WHEN 2,344: BreakPt&(CaretY%) EOR= 1 : Refresh% = TRUE
            WHEN 148,345: BreakPt&() = 0 : Refresh% = TRUE
              
            WHEN 360,145: PROCtopics
            WHEN 361: PROCtutorial
            WHEN 362: PROCemail
            WHEN 363: PROCwebsite
            WHEN 364: PROCdiscuss
            WHEN 365: PROCforum
            WHEN 366: PROCwiki
            WHEN 369: PROCabout : ON
              
            WHEN 370: REM Add REMs
              IF CaretX% <> AnchorX% OR CaretY% <> AnchorY% THEN
                PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
                PROCaddrems(Buffer$(), Indent%(), CaretY%, AnchorY%, nLines%)
                Changed% = TRUE
              ENDIF
            WHEN 371: REM Remove REMs
              IF CaretX% <> AnchorX% OR CaretY% <> AnchorY% THEN
                PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
                PROCremrems(Buffer$(), Indent%(), CaretY%, AnchorY%, nLines%)
                Changed% = TRUE
              ENDIF
            WHEN 372: PROCgoback
            WHEN 373: PROCjumpto(click%(1))
            WHEN 374: ScrollV% -= maxy% - miny%
            WHEN 375: ScrollV% += maxy% - miny%
            WHEN 376: REM click
              PROCpointtochar(click%(1), click%(2))
              CaretX% = click%(1)
              CaretY% = click%(2)
              IF NOT INKEY(-1) THEN
                AnchorX% = CaretX%
                AnchorY% = CaretY%
                SelWord$ = ""
              ENDIF
            WHEN 377: REM drag select
              PROCpointtochar(click%(1), click%(2))
              CaretX% = click%(1)
              CaretY% = click%(2)
            WHEN 378: REM drag scroll
              ScrollH% -= click%(1)
              ScrollV% -= click%(2)
              T% = TRUE
            WHEN 379: PROCcontextmenu(click%(1), click%(2)) : REM Right click
            WHEN 154: PROCcontextmenu(2*@vdu.c.x%, 2*(@vdu%!212-@vdu.c.y%)-@vdu%!220) : REM F10
            WHEN 402: PROCtooltip(click%(1), click%(2)) : REM Hover
            WHEN 5: PROCtooltip(2*@vdu.c.x%, 2*(@vdu%!212-@vdu.c.y%)-@vdu%!220) : REM Ctrl+E
            WHEN 380,155: REM Double-click or F11
              SelWord$ = FNselword
              Refresh% = TRUE
              KeepSelection% = TRUE
            WHEN 390: REM Double-click in breakpoint bar
              BreakPt&((ScrollV% + BrkPtBar.t% - click%(2)) DIV (@vdu%!220 * 2)) EOR= 1
              Refresh% = TRUE
              
            OTHERWISE:
              IF click%(0) >= 32  IF click%(0) < 127  PROCtyped(click%(0)) : Changed% = TRUE : T% = TRUE
              IF click%(0) >= 160 IF click%(0) <= 255 PROCtyped(click%(0)) : Changed% = TRUE : T% = TRUE
              IF click%(0) >= 381 IF click%(0) <= 389 IF FNoktoditch THEN
                PROCload(Recent$(click%(0) MOD 10), nLines%, MaxLen%, FALSE)
                ScrollH% = 0
                ScrollV% = 0
                CaretX% = 0
                CaretY% = 0
                AnchorX% = 0
                AnchorY% = 0
                SelWord$ = ""
                Refresh% = TRUE
              ENDIF
              IF click%(0) >= 391 IF click%(0) <= 399 PROCrunaddin(Addin$(click%(0) MOD 10))
          ENDCASE
          
          IF F% IF INKEY$(-256) = "s"  IF !436 = 0      REPEAT UNTIL INKEY(0) = -1
          IF F% IF INKEY$(-256) <> "s" IF @vdu%?207 = 0 REPEAT UNTIL INKEY(0) = -1
          IF NOT T% Typing% = FALSE
          
        ENDIF
        
        IF nLines% = 0 CaretX% = 0 : CaretY% = 0 : AnchorX% = 0 : AnchorY% = 0
        IF CaretX% > MaxLen% MaxLen% = CaretX%
        IF CaretY% < 0 CaretY% = 0
        IF CaretY% > nLines% CaretY% = nLines%
        IF AnchorY% < 0 AnchorY% = 0
        IF AnchorY% > nLines% AnchorY% = nLines%
        
        IF CaretX%<>oldCaretX% OR CaretY%<>oldCaretY% THEN
          REM Select if drag or shift held down:
          IF NOT INKEY(-1) IF NOT INKEY(-10) IF NOT KeepSelection% THEN
            AnchorX% = CaretX%
            AnchorY% = CaretY%
            SelWord$ = ""
          ENDIF
          REM If caret is moved vertically scroll if necessary to make it visible:
          WHILE ScrollV% - CaretY% * chary% < miny% ScrollV% += chary% : ENDWHILE
          WHILE ScrollV% - CaretY% * chary% > maxy% ScrollV% -= chary% : ENDWHILE
          Refresh% = TRUE
        ENDIF
        KeepSelection% = FALSE
        
        IF ScrollH% < (maxx% - minx%) - MaxLen% * charx% THEN
          ScrollH% = (maxx% - minx%) - MaxLen% * charx%
        ENDIF
        IF ScrollV% > nLines% * chary% - (maxy% - miny%) THEN
          ScrollV% = nLines% * chary% - (maxy% - miny%)
        ENDIF
        IF ScrollH% > 0 ScrollH% = 0
        IF ScrollV% < 0 ScrollV% = 0
        
        IF ScrollH%<>oldScrollH% OR ScrollV%<>oldScrollV% THEN
          oldScrollH% = ScrollH% : oldScrollV% = ScrollV%
          Refresh% = TRUE
        ENDIF
        
        IF AnchorX%<>oldAnchorX% OR AnchorY%<>oldAnchorY% THEN
          oldAnchorX% = AnchorX% : oldAnchorY% = AnchorY%
          Refresh% = TRUE
        ENDIF
        
        IF Changed% THEN
          Changed% = FALSE
          Unsaved% = TRUE
          Refresh% = TRUE
        ENDIF
        
        IF Resized% THEN
          Resized% = FALSE
          WAIT 5
          VDU 26
          IF POS REM SDL thread sync.
          PROCdrawall(@vdu%!208, @vdu%!212)
          Refresh% = TRUE
        ENDIF
        
        IF click%(0) = 137 THEN
        ELSE IF Refresh% THEN;
          Refresh% = FALSE
          *REFRESH OFF
          PROCrefresh(ScrollH%, ScrollV%, CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
          VDU 24,BrkPtBar.l%;BrkPtBar.b%;BrkPtBar.r%;BrkPtBar.t%;
          GCOL COL_GUIBKGD + 128 : CLG : GCOL COL_SELECT
          T% = @vdu%!220 * 2
          I% = ScrollV% DIV T%
          Y% = BrkPtBar.t% + ScrollV% MOD T% - T% DIV 3
          REPEAT
            IF BreakPt&(I%) RECTANGLE FILL 8,Y%,12,-12
            I% += 1
            Y% -= T%
          UNTIL Y% < BrkPtBar.b%
          VDU 24,0;0;@vdu%!208*2-2;@vdu%!212*2-2;
          
          REM If caret is moved horizontally scroll if necessary to make it visible:
          IF CaretX%<>oldCaretX% OR CaretY%<>oldCaretY% THEN
            oldCaretX% = CaretX% : oldCaretY% = CaretY%
            caretxpos% = @vdu.c.x% * 2 - EditRect.l% - ScrollH%
            WHILE ScrollH% + caretxpos% < minx% ScrollH% += charx% : Refresh% = TRUE : ENDWHILE
            WHILE ScrollH% + caretxpos% > maxx% ScrollH% -= charx% : Refresh% = TRUE : ENDWHILE
          ENDIF
          
          IF NOT Refresh% THEN
            *REFRESH
            *REFRESH ON
          ENDIF
        ELSE
          WAIT 1 : REM For minimum ON SYS and ON MOUSE latency
          WAIT 1
          WAIT 1
          WAIT 1
          WAIT 1
        ENDIF
        
      UNTIL FALSE
      END
      
      REM!Eject --------------------------------------------------------------------------
      DEF ___Event_Handlers___
      
      REM ON MOUSE handler:
      DEF PROCmouse(W%, L%)
      LOCAL X%, Y%
      IF TIME < ScrollTime% ENDPROC
      ON TIME LOCAL OFF
      
      X% = 2*(L% AND &FFFF) : Y% = 2*(@vdu%!212 - (L% >>> 16))
      IF FN_ptinrect(X%, Y%, EditRect{}) THEN
        IF W% AND 2 THEN
          Click%() = 379, X%, Y%
        ELSE
          IF TIME > DblClkTime% THEN
            Dragging% = 1
            Click%() = 376, X%, Y%
          ELSE
            Dragging% = 0
            Click%() = 380, X%, Y%
          ENDIF
        ENDIF
        DblClkTime% = TIME + DBLCLICK
      ELSE IF FN_ptinrect(X%, Y%, BrkPtBar{}) THEN;
        IF TIME <= DblClkTime% Click%() = 390, X%, Y%
        DblClkTime% = TIME + DBLCLICK
      ELSE
        PROCclick(FNhotspot(X%, Y%))
      ENDIF
      ENDPROC
      
      DEF PROCclick(L%)
      LOCAL H%, Y%
      Y% = 2*@vdu%!212 - MENUBARHEIGHT + 2
      REPEAT
        H% = 0
        CASE L% OF
          WHEN IDVSCRL: Dragging% = 2
          WHEN IDHSCRL: Dragging% = 3
          WHEN IDPAGER: Repeating% = 158 : RepTimer% = 0 : Click%() = 158,0,0
          WHEN IDPAGEL: Repeating% = 159 : RepTimer% = 0 : Click%() = 159,0,0
          WHEN IDPAGED: Repeating% = 374 : RepTimer% = 0 : Click%() = 374,0,0
          WHEN IDPAGEU: Repeating% = 375 : RepTimer% = 0 : Click%() = 375,0,0
          WHEN IDSCRLL: Repeating% = 142 : RepTimer% = 0 : Click%() = 142,0,0
          WHEN IDSCRLR: Repeating% = 143 : RepTimer% = 0 : Click%() = 143,0,0
          WHEN IDSCRLU: Repeating% = 146 : RepTimer% = 0 : Click%() = 146,0,0
          WHEN IDSCRLD: Repeating% = 144 : RepTimer% = 0 : Click%() = 144,0,0
          WHEN IDCOMBO: Click%() = 334,0,0
          WHEN IDMENU1: H% = FNmenu(L%,FileMenu$(),FileMenu%(),MenuPos%(0),Y%)
          WHEN IDMENU2: H% = FNmenu(L%,EditMenu$(),EditMenu%(),MenuPos%(1),Y%)
          WHEN IDMENU3: H% = FNmenu(L%,UtilMenu$(),UtilMenu%(),MenuPos%(2),Y%)
          WHEN IDMENU4: H% = FNmenu(L%,OptsMenu$(),OptsMenu%(),MenuPos%(3),Y%)
          WHEN IDMENU5: H% = FNmenu(L%,RunMenu$(), RunMenu%(), MenuPos%(4),Y%)
          WHEN IDMENU6: H% = FNmenu(L%,HelpMenu$(),HelpMenu%(),MenuPos%(5),Y%)
          OTHERWISE: IF L% >= 0 IF L% < NBUTTONS Pressed% = ToolCmd%(L%)
        ENDCASE
        IF H% > 0 Click%() = H%,0,0 : H% = 0
        IF H% = -136: L% = (L%-IDMENU1+NMENUS-1) MOD NMENUS + IDMENU1 : PROChilite(L%)
        IF H% = -137: L% = (L%-IDMENU1+NMENUS+1) MOD NMENUS + IDMENU1 : PROChilite(L%)
      UNTIL H% = 0
      ENDPROC
      
      REM ON TIME handler:
      DEF PROCtimer(F%) : LOCAL $$Accs%% : REM For tokenizer
      LOCAL B%, X%, Y%, olddebug%
      PRIVATE oldx%, oldy%, oldb%, oldalt%, oldlin%, olderr%, selection%, telltale%, hilerr%
      PRIVATE cliptext%, unsaved%, canundo%, canredo%, anyprog%, debugging%, oldpause%, drag%
      
      REM Check for ALT key state change:
      B% = INKEY(-6) AND NOT INKEY(-5)
      IF B% <> oldalt% THEN
        oldalt% = B%
        IF B% PROCaltmode
      ENDIF
      
      REM Test for any program:
      B% = nLines% <> 0
      IF B% <> anyprog% THEN
        anyprog% = B%
        TBenable&(11) = B% : REM Renumber button
        TBenable&(12) = B% : REM Compile button
        UtilMenu%(0) = UtilMenu%(0) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Renumber menu
        UtilMenu%(1) = UtilMenu%(1) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Compile menu
        UtilMenu%(3) = UtilMenu%(3) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM List DEFs menu
      ENDIF
      
      REM Test for selection:
      B% = CaretX% <> AnchorX% OR CaretY% <> AnchorY%
      IF B% <> selection% THEN
        selection% = B%
        TBenable&(6) = B% : REM Cut button
        TBenable&(7) = B% : REM Copy button
        EditMenu%(3) = EditMenu%(3) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Cut menu
        EditMenu%(4) = EditMenu%(4) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Copy menu
        EditMenu%(6) = EditMenu%(6) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Delete menu
        F% = TRUE
      ENDIF
      
      REM Test for clipboard text:
      B% = FNhascliptext
      IF B% <> cliptext% THEN
        cliptext% = B%
        TBenable&(8) = B% : REM Paste button
        EditMenu%(5) = EditMenu%(5) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Paste menu
        F% = TRUE
      ENDIF
      
      REM Test for program being unsaved:
      B% = Unsaved%
      IF B% <> unsaved% THEN
        unsaved% = B%
        TBenable&(2) = B% : REM Save button
        FileMenu%(2) = FileMenu%(2) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Save menu
        F% = TRUE
      ENDIF
      
      REM Test for being able to undo:
      B% = UndoLevel% <> 0
      IF B% <> canundo% THEN
        canundo% = B%
        TBenable&(4) = B% : REM Undo button
        EditMenu%(0) = EditMenu%(0) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Undo menu
        F% = TRUE
      ENDIF
      
      REM Test for being able to redo:
      B% = RedoLevel% > UndoLevel%
      IF B% <> canredo% THEN
        canredo% = B%
        TBenable&(5) = B% : REM Redo button
        EditMenu%(1) = EditMenu%(1) AND NOT &1000 OR &1000 AND (B%=FALSE) : REM Redo menu
        F% = TRUE
      ENDIF
      
      REM Check menu items:
      OptsMenu%(0) = OptsMenu%(0) AND NOT &2000 OR &2000 AND Colouring%
      OptsMenu%(1) = OptsMenu%(1) AND NOT &2000 OR &2000 AND Lowercase%
      OptsMenu%(2) = OptsMenu%(2) AND NOT &2000 OR &2000 AND Indentation%
      OptsMenu%(3) = OptsMenu%(3) AND NOT &2000 OR &2000 AND Unicode%
      OptsMenu%(4) = OptsMenu%(4) AND NOT &2000 OR &2000 AND Abbrev%
      OptsMenu%(8) = OptsMenu%(8) AND NOT &2000 OR &2000 AND Tooltips%
      OptsMenu%(9) = OptsMenu%(9) AND NOT &2000 OR &2000 AND Darkmode%
      UtilMenu%(4) = UtilMenu%(4) AND NOT &2000 OR &2000 AND IncludeON%
      UtilMenu%(5) = UtilMenu%(5) AND NOT &2000 OR &2000 AND IncludeLab%
      UtilMenu%(6) = UtilMenu%(6) AND NOT &2000 OR &2000 AND SortList%
      
      REM Check for trace and list variables:
      olddebug% = (debugging% <> 0)
      B% = OPENIN(@tmp$ + "sdldebug.dat")
      IF B% THEN
        X% = BGET#B% OR (BGET#B% << 8) OR (BGET#B% << 16) OR (BGET#B% << 24)
        Y% = BGET#B% OR (BGET#B% << 8) OR (BGET#B% << 16) OR (BGET#B% << 24)
        IF debugging% IF X% <> oldlin% OR Y% <> olderr% THEN
          oldlin% = X%
          IF Y% <> olderr% IF Y% > BBCPtr%(0) hilerr% = 10
          IF hilerr% hilerr% -= 1 : X% = Y% : REM Error has priority in highlighting
          olderr% = Y%
          Y% = FNchop(BBCPtr%(), X%)
          IF Y% < &FFFF THEN
            CaretX% = 0 : CaretY% = Y%
            AnchorX% = 0 : AnchorY% = Y%+1
            KeepSelection% = TRUE
          ELSE
            AnchorX% = CaretX%
            AnchorY% = CaretY%
          ENDIF
          Refresh% = TRUE
        ENDIF
        X% = BGET#B% OR 1 : REM Must be non-zero
        Y% = BGET#B% AND 3 : REM Single-step and profiling flags
        IF X% <> telltale% THEN
          IF telltale% debugging% = 20
          telltale% = X%
        ENDIF
        CLOSE #B%
      ELSE
        Y% = oldpause%
      ENDIF
      IF debugging% debugging% -= 1
      
      REM Test for debugging:
      IF olddebug% <> (debugging% <> 0) THEN
        TBenable&(15) = debugging% <> 0 : REM Stop button
        TBenable&(16) = debugging% <> 0 : REM Pause button
        RunMenu%(3) = RunMenu%(3) AND NOT &1000 OR &1000 AND debugging%=0 : REM Stop menu
        RunMenu%(4) = RunMenu%(4) AND NOT &1000 OR &1000 AND debugging%=0 : REM Pause menu
        IF debugging% THEN
          IF (Y% AND 1) = 0 PROCexecute(@dir$ + "listvars.bbc", "-hidden" + FNdark)
        ELSE
          IF (Y% AND 1) = 1 PROCexecute(@dir$ + "profiler.bbc", "-hidden" + FNdark)
          AnchorY% = CaretY% : Refresh% = TRUE
          oldlin% = 0 : olderr% = 0 : hilerr% = 0
        ENDIF
        F% = TRUE
      ENDIF
      
      REM Check for pause:
      IF debugging% = 0 Y% = 0
      B% = (Y% AND 2) <> 0
      IF B% <> oldpause% THEN
        oldpause% = B%
        TBpressed&(16) = B%
        TBenable&(17) = B% : REM Step into button
        TBenable&(18) = B% : REM Step over button
        RunMenu%(5) = RunMenu%(5) AND NOT &1000 OR &1000 AND NOT B% : REM Step into menu
        RunMenu%(6) = RunMenu%(6) AND NOT &1000 OR &1000 AND NOT B% : REM Step over menu
        F% = TRUE
        PROChilite(-1)
      ENDIF
      
      REM Check mouse:
      MOUSE X%, Y%, B%
      IF ABS(X% - oldx%) < 5 IF ABS(Y% - oldy%) < 5 Hover% += 1 ELSE Hover% = 0
      IF Tooltips% IF Hover% > Hovertime% Hover% = -10000 : Click%() = 402, X%, Y%
      
      IF B% = 0 Dragging% = 0 : Repeating% = FALSE
      IF B% = 0 IF Pressed% Click%() = Pressed%,0,0 : Pressed% = FALSE
      
      IF Repeating% THEN
        RepTimer% += 1
        IF RepTimer% > DELAY Click%() = Repeating%,0,0
      ENDIF
      
      CASE Dragging% OF
        WHEN 1:
          IF Click%(0) = TRUE IF X% <> oldx% OR Y% <> oldy% Click%() = 377, X%, Y%
        WHEN 2:
          Click%() = 378, 0, (Y% - oldy%) * ScrlBarV.scale
        WHEN 3:
          Click%() = 378, (X% - oldx%) * ScrlBarH.scale, 0
      ENDCASE
      
      IF NOT F% IF X% = oldx% IF Y% = oldy% IF B% = oldb% ENDPROC
      oldx% = X% : oldy% = Y% : oldb% = B%
      
      IF FN_ptinrect(X%, Y%, EditRect{}) THEN
        PROCcursor(1)
      ELSE
        IF X% >= 0 IF X% <= 2*@vdu%!208 IF Y% >= 0 IF Y% < 2*@vdu%!212 PROCcursor(0)
      ENDIF
      
      IF Dragging% <> drag% THEN
        drag% = Dragging%
        IF NOT BB4W% SYS "SDL_CaptureMouse", Dragging% <> 0, @memhdc%
      ENDIF
      
      IF Dragging% = 0 PROChilite(FNhotspot(X%, Y%))
      ENDPROC
      
      REM ON MOVE handler:
      DEF PROCmove(M%, W%, L%)
      IF M% <> WM_SIZE ENDPROC
      Resized% = TRUE
      ENDPROC
      
      DEF PROCaltmode
      LOCAL K%,L%,M%
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      L% = IDMENU1
      REPEAT
        IF BB4W% SYS "GetForegroundWindow" TO K% : IF K% <> @hwnd% ENDPROC
        IF NOT BB4W% SYS "SDL_GetWindowFlags", @hwnd%, @memhdc% TO K% : IF (K% AND &200)=0 ENDPROC
        IF M% = 0 IF INKEY(-18) OR INKEY(-26) OR INKEY(-122) OR INKEY(-48) OR INKEY(-90) ENDPROC
        IF NOT INKEY(-3) IF M% = 0 M% = 1 : PROChilite(L%)
        IF INKEY(-3)     IF M% = 1 M% = 2 : PROChilite(-1)
        IF NOT INKEY(-3) IF M% = 2 EXIT REPEAT
        IF M% = 1 THEN
          CASE INKEY(1) OF
            WHEN 27:     PROChilite(-1) : ENDPROC
            WHEN 13,138: PROCclick(L%)  : ENDPROC
            WHEN 136:    L% = (L%-IDMENU1+NMENUS-1) MOD NMENUS + IDMENU1 : PROChilite(L%)
            WHEN 137:    L% = (L%-IDMENU1+NMENUS+1) MOD NMENUS + IDMENU1 : PROChilite(L%)
          ENDCASE
        ENDIF
        FOR K% = 0 TO NMENUS-1
          IF INKEY(-MenuKey&(K%)) PROChilite(IDMENU1+K%) : PROCclick(IDMENU1+K%) : ENDPROC
        NEXT
      UNTIL FALSE
      ENDPROC
      
      DEF PROCscroll(L%)
      PRIVATE oldx%, oldy%, sema4%
      IF sema4% ENDPROC
      sema4% = TRUE
      LOCAL X%, Y%
      X% = (L% << 16) >> 16
      Y% = L% >> 16
      IF TIME < ScrollTime% THEN
        ScrollH% += (X% - oldx%) * 2
        ScrollV% -= (Y% - oldy%) * 2
      ENDIF
      oldx% = X% : oldy% = Y%
      ScrollTime% = TIME + 10
      sema4% = FALSE
      ENDPROC
      
      REM!Eject --------------------------------------------------------------------------
      DEF __Text_Editing__
      
      DEF PROCwordleft
      LOCAL I%, a$, l$, r$
      I% = Indent%(CaretY%)
      a$ = FNstrip(FNformat(Buffer$(CaretY%), I%))
      PROCsplit(a$, CaretX%, l$, r$)
      WHILE CaretX% > 0 AND RIGHT$(l$) = " "
        CaretX% -= 1
        PROCsplit(a$, CaretX%, l$, r$)
      ENDWHILE
      IF CaretX% = 0 ENDPROC
      REPEAT
        CaretX% -= 1
        PROCsplit(a$, CaretX%, l$, r$)
      UNTIL INSTR(Valid$, RIGHT$(l$)) = 0
      ENDPROC
      
      DEF PROCwordright
      LOCAL I%, a$, l$, r$
      I% = Indent%(CaretY%)
      a$ = FNstrip(FNformat(Buffer$(CaretY%), I%))
      REPEAT
        IF CaretX% >= FNlen(a$) ENDPROC
        PROCsplit(a$, CaretX%, l$, r$)
        CaretX% += 1
      UNTIL INSTR(Valid$, LEFT$(r$,1)) = 0
      WHILE CaretX% < FNlen(a$) AND MID$(r$,2,1) = " "
        PROCsplit(a$, CaretX%, l$, r$)
        CaretX% += 1
      ENDWHILE
      ENDPROC
      
      REM Selected word is allowed to contain colour-change codes, except at start
      DEF FNselword
      LOCAL I%, a$, l$, r$
      I% = Indent%(CaretY%)
      a$ = FNformat(Buffer$(CaretY%), I%)
      AnchorX% = CaretX% : AnchorY% = CaretY%
      PROCsplit(a$, CaretX%, l$, r$)
      WHILE CaretX% < FNlen(a$) AND INSTR(Valid$ + "@_`#$%&", LEFT$(r$,1))
        CaretX% += 1
        PROCsplit(a$, CaretX%, l$, r$)
      ENDWHILE
      PROCsplit(a$, AnchorX%, l$, r$)
      WHILE AnchorX% > 0 AND INSTR(Valid$ + "@_`", RIGHT$(l$))
        AnchorX% -= 1
        PROCsplit(a$, AnchorX%, l$, r$)
      ENDWHILE
      PROCsplit(r$, CaretX% - AnchorX%, l$, r$)
      IF ASCl$ = &12 l$ = MID$(l$,4)
      = l$
      
      DEF PROCbackspace(F%) : IF nLines% = 0 ENDPROC
      LOCAL D%, I%, p%%, a$, l$, r$
      IF NOT Typing% THEN
        Typing% = TRUE
        PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
      ENDIF
      IF F% PROCwordleft
      IF AnchorX%<>CaretX% OR AnchorY%<>CaretY% THEN
        PROCdeltext(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
      ELSE IF CaretX% THEN;
        I% = Indent%(CaretY%)
        a$ = FNformat(Buffer$(CaretY%), I%)
        PROCsplit(a$, CaretX%-1, l$, r$)
        PROCsplit(a$, CaretX%, a$, r$)
        CaretX% -= 1
        PROCreformat(l$ + r$, CaretX%, CaretY%, Buffer$(), Indent%(), TRUE)
      ELSE IF CaretY% IF CaretY% <= nLines% THEN;
        I% = Indent%(CaretY%-1)
        l$ = FNformat(Buffer$(CaretY%-1), I%)
        r$ = FNformat(Buffer$(CaretY%), I%)
        D% = I% - Indent%(CaretY%)
        PROCreformat(l$ + r$, CaretX%, CaretY%-1, Buffer$(), Indent%(), TRUE)
        CaretX% = FNlen(l$)
        p%% = ^Buffer$(CaretY%)
        FOR I% = CaretY% TO nLines%
          Indent%(I%) = Indent%(I%+1) - D%
          BreakPt&(I%) = BreakPt&(I%+1)
          p%%!0 = p%%!8 : p%%!4 = p%%!12
          p%% += 8
        NEXT
        p%%!0 = 0 : p%%!4 = 0
        IF CaretY% < nLines% OR LENBuffer$(nLines%-1) <= 4 THEN
          nLines% -= 1
          CaretY% -= 1
        ELSE
          CaretX% = 0
        ENDIF
      ENDIF
      Buffer$(nLines%) = ""
      AnchorX% = CaretX%
      AnchorY% = CaretY%
      ENDPROC
      
      DEF PROCdelete(F%) : IF nLines% = 0 ENDPROC
      LOCAL I%, a$, l$, r$
      IF NOT Typing% THEN
        Typing% = TRUE
        PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
      ENDIF
      IF F% PROCwordright
      IF AnchorX%<>CaretX% OR AnchorY%<>CaretY% THEN
        PROCdeltext(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
      ELSE
        I% = Indent%(CaretY%)
        a$ = FNformat(Buffer$(CaretY%), I%)
        PROCsplit(a$, CaretX%, l$, r$)
        PROCsplit(a$, CaretX%+1, a$, r$)
        PROCreformat(l$ + r$, CaretX%, CaretY%, Buffer$(), Indent%(), FALSE)
      ENDIF
      ENDPROC
      
      DEF PROCreturn : IF nLines% = 0 ENDPROC
      LOCAL I%, p%%, a$, l$, r$
      IF NOT Typing% THEN
        Typing% = TRUE
        PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
      ENDIF
      PROCdeltext(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
      I% = Indent%(CaretY%)
      a$ = FNformat(Buffer$(CaretY%), I%)
      PROCsplit(a$, CaretX%, l$, r$)
      p%% = ^Buffer$(nLines%)
      FOR I% = nLines% TO CaretY% STEP -1
        Indent%(I%+1) = Indent%(I%)
        BreakPt&(I%+1) = BreakPt&(I%)
        p%%!8 = p%%!0 : p%%!12 = p%%!4
        p%% -= 8
      NEXT
      p%%!8 = 0 : p%%!12 = 0
      nLines% += 1
      PROCreformat(l$, CaretX%, CaretY%, Buffer$(), Indent%(), FALSE)
      CaretY% += 1
      PROCreformat(r$, CaretX%, CaretY%, Buffer$(), Indent%(), FALSE)
      CaretX% = 0
      AnchorX% = CaretX%
      AnchorY% = CaretY%
      ENDPROC
      
      DEF PROCtyped(K%)
      LOCAL U%, k$
      IF NOT Typing% THEN
        Typing% = TRUE
        PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
      ENDIF
      PROCdeltext(Buffer$(), Indent%(), BreakPt&(), CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
      U% = K%
      REPEAT
        k$ += CHR$K%
        K% = INKEY(1)
      UNTIL K% < &20 OR K% >= &80 AND K% < &A0 AND U% < &C0
      IF K% <> -1 Click%() = K%, 0, 0
      IF BB4W% OR Unicode% ELSE k$ = FN_utf8_to_ansi(k$)
      IF BB4W% IF Unicode% THEN k$ = FN_ansi_to_utf8(k$)
      IF Overtype% THEN
        PROCovertype(Buffer$(), Indent%(), CaretX%, CaretY%, k$)
      ELSE
        PROCinsert(Buffer$(), Indent%(), CaretX%, CaretY%, k$)
      ENDIF
      IF CaretY% >= nLines% nLines% = CaretY% + 1
      AnchorX% = CaretX%
      AnchorY% = CaretY%
      ENDPROC
      
      REM!Eject --------------------------------------------------------------------------
      DEF __Menu_Handlers__
      
      DEF __File_Menu__
      
      REM File... New
      DEF PROCnew
      CurrentFile$ = ""
      Buffer$() = ""
      Indent%() = 0
      BreakPt&() = 0
      MaxLen% = 0
      CaretX% = 0
      CaretY% = 0
      AnchorX% = 0
      AnchorY% = 0
      nLines% = 0
      Refresh% = TRUE
      PROCundoclear(UndoLevel%, RedoLevel%)
      PROCtitle("(untitled)")
      PROC_setdlgitemtext(FileDlg%, 104, "")
      ENDPROC
      
      REM File... Load
      DEF PROCload
      LOCAL f$
      f$ = FNfileselector("Load File")
      IF f$ = "" ENDPROC
      PROCload(f$, nLines%, MaxLen%, FALSE)
      BreakPt&() = 0
      ScrollH% = 0
      ScrollV% = 0
      CaretX% = 0
      CaretY% = 0
      AnchorX% = 0
      AnchorY% = 0
      Hover% = -10000
      ENDPROC
      
      REM File... Insert
      DEF FNinsertfile
      LOCAL f$
      f$ = FNfileselector("Insert File")
      IF f$ = "" THEN = FALSE
      PROCload(f$, nLines%, MaxLen%, TRUE)
      = TRUE
      
      REM File... Compare
      DEF PROCcomparefile
      LOCAL f$
      f$ = FNfileselector("Compare File")
      IF f$ = "" ENDPROC
      PROCcompare(f$)
      ENDPROC
      
      REM File... Print
      DEF PROCprintprogram
      LOCAL F%, I%, N%, R%, a$, file$
      IF CurrentFile$ = "" THEN
        file$ = @tmp$ + "untitled.txt"
      ELSE
        file$ = @tmp$ + FNnopath(CurrentFile$) + ".txt"
      ENDIF
      F% = OPENOUT(file$)
      I% = Indent%(0)
      FOR N% = 0 TO nLines% - 1
        a$ = FNstrip(FNformat(Buffer$(N%), I%))
        PRINT #F%, a$
        BPUT #F%, 10
        IF INSTR(a$, "REM!Eject") BPUT #F%,12
      NEXT
      CLOSE #F%
      R% = FNmessagebox("SDLIDE", "Send listing to default printer?", MB_ICONQUESTION + MB_YESNO)
      IF R% = IDYES THEN
        PROCcursor(2)
        IF NOT BB4W% IF @platform% AND &F THEN
          OSCLI "RUN lp -c """ + file$ + """"
        ELSE
          SYS "ShellExecuteA", @hwnd%, "print", file$, 0, 0, 0
        ENDIF
        WAIT 200
        PROCcursor(0)
      ENDIF
      OSCLI "DELETE """ + file$ + """"
      ENDPROC
      
      REM File... Save
      DEF FNsave
      LOCAL R%
      IF CurrentFile$ = "" THEN = FNsaveas
      R% = FNsave(CurrentFile$)
      IF R% PROCupdaterecent(CurrentFile$)
      = R%
      
      REM File... Save As
      DEF FNsaveas
      LOCAL F%, R%, a$
      F% = FNinstrr(Recent$(1), "/", 0)
      IF F% = 0 F% = FNinstrr(Recent$(1), "\", 0)
      ON ERROR LOCAL IF FALSE THEN
        IF F% THEN
          OSCLI "cd """ + LEFT$(Recent$(1), F%-1) + """"
        ELSE
          OSCLI "cd """ + LEFT$(@usr$) + """"
        ENDIF
      ENDIF : RESTORE ERROR
      a$ = FNfileselector("Save File")
      IF a$ = "" THEN = FALSE
      F% = OPENIN(a$)
      IF F% THEN
        CLOSE #F%
        R% = FNmessagebox("SDLIDE", FNnopath(a$) + " already exists," + CHR$13 + CHR$10 + \
        \    "do you want to replace it?", MB_ICONQUESTION + MB_YESNO)
        IF R% <> IDYES THEN = FALSE
      ENDIF
      CurrentFile$ = a$
      PROCtitle(CurrentFile$)
      = FNsave
      
      REM File... Exit
      DEF FNexit
      LOCAL maximized%
      IF BB4W% THEN
        SYS "IsZoomed", @hwnd% TO maximized%
      ELSE
        SYS "SDL_GetWindowFlags", @hwnd% TO maximized%
        maximized% AND= &80
      ENDIF
      IF maximized% THEN
        PROCputINIstring(IniFile$, "maximized", "1")
      ELSE
        PROCputINIstring(IniFile$, "maximized", "0")
        PROCputINIstring(IniFile$, "windowwidth", STR$@vdu%!208)
        PROCputINIstring(IniFile$, "windowheight", STR$@vdu%!212)
      ENDIF
      PROCputINIstring(IniFile$, "colouring", STR$(Colouring% <> 0))
      PROCputINIstring(IniFile$, "indentation", STR$(Indentation% <> 0))
      PROCputINIstring(IniFile$, "lowercase", STR$(Lowercase% <> 0))
      PROCputINIstring(IniFile$, "abbreviations", STR$(Abbrev% <> 0))
      PROCputINIstring(IniFile$, "tooltips", STR$(Tooltips% <> 0))
      PROCputINIstring(IniFile$, "darkmode", STR$(Darkmode% <> 0))
      PROCputINIstring(IniFile$, "unicode", STR$(Unicode% <> 0))
      PROCputINIstring(IniFile$, "includeon", STR$(IncludeON% <> 0))
      PROCputINIstring(IniFile$, "includelab", STR$(IncludeLab% <> 0))
      PROCputINIstring(IniFile$, "sortlist", STR$(SortList% <> 0))
      PROCputINIstring(IniFile$, "guiscale", STR$(GUIscale))
      PROCputINIstring(IniFile$, "guifont", GUIFont$)
      PROCputINIstring(IniFile$, "editfont", EditFont$)
      
      FOR i% = 1 TO 9
        PROCputINIstring(IniFile$, "recent" + STR$(i%), Recent$(i%))
      NEXT
      
      FOR i% = 1 TO 6
        IF Darkmode% THEN
          PROCputINIstring(IniFile$, "dark" + STR$(i%), STR$(Colours%(i%-1)))
        ELSE
          PROCputINIstring(IniFile$, "colour" + STR$(i%), STR$(Colours%(i%-1)))
        ENDIF
      NEXT
      
      = TRUE
      
      DEF __Edit_Menu__
      
      REM Edit... Undo
      REM Edit... Redo
      DEF PROCundoundo(f$(), i%(), b&(), RETURN nl%, ul%, RETURN cx%, RETURN cy%)
      LOCAL F%,I%,L%,N%
      ON TIME LOCAL OFF
      PROCcursor(2)
      f$() = ""
      F% = OPENIN(@tmp$ + "undo" + Session$ + STR$ul% + ".tmp.bbc")
      REPEAT
        i%(N%) = I%
        L% = BGET#F% : IF L% = 0 EXIT REPEAT
        f$(N%) = CHR$L% + GET$#F% BY 2 + GET$#F% TO &D + CHR$&D
        PROCindent(f$(N%), I%, L%)
        N% += 1
      UNTIL FALSE
      INPUT #F%, cx%, cy%, $^b&(0) : b&(LEN$^b&(0)) = 0
      CLOSE #F%
      nl% = N%
      PROCcursor(1)
      ENDPROC
      
      REM Edit... Copy:
      DEF PROCcopytext(f$(), i%(), x1%, y1%, x2%, y2%)
      LOCAL H%, T%, a$
      a$ = FNseltext(f$(), i%(), x1%, y1%, x2%, y2%)
      IF NOT Unicode% a$ = FN_ansi_to_utf8(a$)
      IF BB4W% THEN
        SYS "GlobalAlloc", &2000, 2*LEN(a$)+2 TO H%
        SYS "GlobalLock", H% TO T%
        SYS "MultiByteToWideChar", CP_UTF8, 0, a$, -1, T%, LEN(a$)+1
        SYS "GlobalUnlock", H%
        SYS "OpenClipboard", @hwnd%
        SYS "EmptyClipboard"
        SYS "SetClipboardData", 13, H%
        SYS "CloseClipboard"
      ELSE
        SYS "SDL_SetClipboardText", a$
      ENDIF
      ENDPROC
      
      REM Edit... Paste
      DEF PROCpaste(f$(), i%(), b&(), RETURN cx%, RETURN cy%, RETURN nl%, RETURN ml%)
      LOCAL H%, I%, N%, p%%, T%, Y%, t%%, a$, l$, r$
      IF cy% < nl% THEN
        I% = i%(cy%)
        a$ = FNstrip(FNformat(f$(cy%), I%))
        PROCsplitx(a$, cx%, l$, r$)
      ENDIF
      IF BB4W% THEN
        SYS "OpenClipboard", @hwnd%
        SYS "GetClipboardData", 13 TO H%
        IF H% THEN
          SYS "GlobalLock", H% TO T%
          SYS "WideCharToMultiByte", CP_UTF8, 0, T%, -1, FALSE, 0, FALSE, FALSE TO I%
          a$ = STRING$(I%, " ")
          SYS "WideCharToMultiByte", CP_UTF8, 0, T%, -1, PTR(a$), LEN(a$), FALSE, FALSE
          a$ = LEFT$(a$)
          SYS "GlobalUnlock", H%
        ENDIF
        SYS "CloseClipboard"
      ELSE
        SYS "SDL_GetClipboardText" TO t%%
        IF NOT BB4W% IF @platform% AND &40 ELSE t%% = !^t%%
        a$ = $$t%%
      ENDIF
      IF NOT Unicode% a$ = FN_utf8_to_ansi(a$)
      REPEAT
        I% = FNinstrq(a$, CHR$&C2+CHR$&A0, 0)
        IF I% a$ = LEFT$(a$, I%-1) + " " + MID$(a$, I%+2)
      UNTIL I% = 0
      IF NOT Unicode% THEN
        REPEAT
          I% = INSTR(a$, CHR$&A0)
          IF I% MID$(a$, I%, 1) = " "
        UNTIL I% = 0
      ENDIF
      REPEAT
        I% = INSTR(a$, CHR$&A, I%+1)
        IF I% N% += 1
      UNTIL I% = 0
      IF N% = 0 THEN
        cx% += FNlen(a$)
        PROCreformat(l$ + a$ + r$, cx%, cy%, f$(), i%(), FALSE)
        IF cy% >= nl% nl% = cy% + 1
      ELSE
        nl% += N%
        IF N% THEN
          p%% = ^f$(&FFFF)
          FOR Y% = &FFFF TO cy%+N% STEP -1
            p%%!0 = p%%!(-N%*8)
            p%%!4 = p%%!(4-N%*8)
            i%(Y%) = i%(Y%-N%)
            b&(Y%) = b&(Y%-N%)
            p%% -= 8
          NEXT
          FOR Y% = 1 TO N%
            p%%!0 = 0 : p%%!4 = 0
            p%% -= 8
          NEXT
        ENDIF
        Y% = cy%
        cx% = 0
        cy% += N%
        I% = i%(Y%)
        REPEAT
          T% = INSTR(a$, CHR$&A)
          IF T% THEN
            f$(Y%) = FNtokenise(FNstrip(l$ + LEFT$(a$, T%-1)))
            i%(Y%) = I%
            l$ = FNformat(f$(Y%), I%)
            l$ = ""
            a$ = MID$(a$, T%+1)
            Y% += 1
          ENDIF
        UNTIL T% = 0
        i%(Y%) = I%
        IF a$ <> "" IF Y% = nl% nl% += 1 : cy% += 1
        f$(Y%) = FNtokenise(FNstrip(a$ + r$))
        WHILE Y% <= nl%
          i%(Y%) = I%
          PROCindent(f$(Y%), I%, ml%)
          Y% += 1
        ENDWHILE
      ENDIF
      ENDPROC
      
      REM Edit... Delete:
      DEF PROCdeltext(f$(), i%(), b&(), RETURN cx%, RETURN cy%, RETURN ax%, RETURN ay%, RETURN nl%)
      LOCAL D%, I%, p%%, Y%, a$, l$, r$, x1%, y1%, x2%, y2%
      x1% = cx% : y1% = cy% : x2% = ax% : y2% = ay%
      IF x1% > x2% SWAP x1%,x2%
      IF y1% > y2% SWAP y1%,y2%
      CASE TRUE OF
        WHEN y1% <> y2%:
          D% = y2% - y1%
          I% = i%(y2%) - i%(y1%)
          p%% = ^f$(y1%)
          FOR Y% = y1% TO nl%-1-D%
            p%%!0 = p%%!(8 * D%)
            p%%!4 = p%%!(8 * D% + 4)
            i%(Y%) = i%(Y% + D%) - I%
            b&(Y%) = b&(Y% + D%)
            p%% += 8
          NEXT
          i%(Y%) = i%(Y% + D%) - I%
          b&(Y%) = b&(Y% + D%)
          nl% -= D%
          FOR Y% = nl% TO nl%+D%-1
            p%%!0 = 0 : p%%!4 = 0
            p%% += 8
          NEXT
        WHEN x1% <> x2%:
          I% = i%(y1%)
          a$ = FNformat(f$(y1%), I%)
          PROCsplit(a$, x1%, l$, r$)
          PROCsplit(a$, x2%, a$, r$)
          PROCreformat(l$ + r$, x1%, y1%, f$(), i%(), FALSE)
      ENDCASE
      IF cy% <> ay% THEN
        cx% = 0 : ax% = 0
      ELSE
        cx% = x1% : ax% = x1%
      ENDIF
      cy% = y1% : ay% = y1%
      ENDPROC
      
      REM Edit... Find
      REM Edit... Replace
      DEF PROCfind    : LOCAL dlg% : dlg% = FindDlg%
      DEF PROCreplace : LOCAL dlg% : dlg% = ReplDlg%
      LOCAL H%, R%, X%, Y%, W%, charx%, chary%, minx%, maxx%, miny%, maxy%, crtx%, find$, repl$
      
      charx% = 2 * @vdu%!216
      chary% = 2 * @vdu%!220
      minx% = 0
      maxx% = EditRect.r% - EditRect.l%
      miny% = EditRect.b% - EditRect.t% + chary%
      maxy% = 0
      
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      
      OSCLI "FONT " + GUIFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      
      find$ = FNseltext(Buffer$(), Indent%(), CaretX%, CaretY%, AnchorX%, AnchorY%)
      IF find$ <> "" THEN
        PROC_setdlgitemtext(dlg%, 103, find$)
        PROC_enabledlgitem(dlg%, 1, TRUE)
        PROC_enabledlgitem(dlg%, 3, TRUE)
        PROC_enabledlgitem(dlg%, 4, TRUE)
      ENDIF
      
      PROC_registerdlgcallback(dlg%, FNfrcb())
      PROC_getdlgrect(dlg%, X%, Y%, W%, H%)
      X% = EditRect.r% - W% : Y% = EditRect.t%
      REPEAT
        R% = FN_showdialogex(dlg%, X%, Y%, Darkmode%)
        PROC_getdlgrect(dlg%, X%, Y%, W%, H%)
        IF R% <> 2 THEN
          FindFlags% = R% : REM 1 = find next, 3 = replace, 4 = replace all
          find$ = FN_getdlgitemtext(dlg%, 103)
          repl$ = FN_getdlgitemtext(dlg%, 104)
          IF FN_isdlgitemchecked(dlg%, 105) FindFlags% OR= &10000
          IF FN_isdlgitemchecked(dlg%, 106) FindFlags% OR= &20000
          PROCsavejump(GoBack%(), ScrollV%, BackLevel%)
          IF (FindFlags% AND 7) = 1 OR (FindFlags% AND 7) = 4 OR CaretX% = AnchorX% THEN
            IF NOT FNsearch(find$, Buffer$(), Indent%(), nLines%, FindFlags%, \
            \               AnchorX%, AnchorY%, CaretX%, CaretY%) THEN
              FindFlags% AND= &30000
              PROCmessagebox("SDLIDE", "String not found", MB_ICONINFORMATION)
              CaretX% = 0 : CaretY% = 0 : AnchorX% = 0 : AnchorY% = 0
            ENDIF
          ENDIF
          IF (FindFlags% AND 7) >= 3 THEN
            PROCundosave(Buffer$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
            REPEAT
              crtx% = CaretX%
              PROCinsert(Buffer$(), Indent%(), CaretX%, CaretY%, repl$)
              PROCdeltext(Buffer$(), Indent%(), BreakPt&(), crtx%, CaretY%, AnchorX%, AnchorY%, nLines%)
              CaretX% = crtx% + FNlen(repl$)
              IF NOT FNsearch(find$, Buffer$(), Indent%(), nLines%, FindFlags%, \
              \               AnchorX%, AnchorY%, CaretX%, CaretY%) FindFlags% AND= &30000
              Changed% = TRUE
            UNTIL (FindFlags% AND 7) < 4
          ENDIF
          
          *REFRESH OFF
          PROC_closedialog(dlg%)
          OSCLI "FONT " + EditFont$
          WHILE ScrollV% - CaretY% * chary% < miny% ScrollV% += chary% : ENDWHILE
          WHILE ScrollV% - CaretY% * chary% > maxy% ScrollV% -= chary% : ENDWHILE
          WHILE ScrollH% + CaretX% * charx% < minx% ScrollH% += charx% : ENDWHILE
          WHILE ScrollH% + CaretX% * charx% > maxx% ScrollH% -= charx% : ENDWHILE
          PROCrefresh(ScrollH%, ScrollV%, CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
          OSCLI "FONT " + GUIFont$
          VDU 23,0,10,0,0;0;0; : REM Set start line
          VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
          VDU 23,0,18,2,0;0;0; : REM Set cursor width
        ENDIF
      UNTIL R% = 2
      *REFRESH ON
      Refresh% = TRUE
      PROC_closedialog(dlg%)
      
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      ENDPROC
      
      DEF FNfrcb(D%, K%)
      LOCAL R%, a$
      PRIVATE E%
      R% = FN_getdlgfocus(D%) : IF R% > 9 R% = 1
      IF K% = 13 THEN = R%
      IF K% = 27 THEN = 2
      a$ = FN_getdlgitemtext(D%, 103)
      IF E% <> (a$ <> "") THEN
        E% = (a$ <> "")
        PROC_enabledlgitem(D%, 1, E%)
        PROC_enabledlgitem(D%, 3, E%)
        PROC_enabledlgitem(D%, 4, E%)
        PROC_refreshdialog(D%)
      ENDIF
      = 0
      
      REM Edit... Find Next
      DEF PROCfindnext
      PROCsavejump(GoBack%(), ScrollV%, BackLevel%)
      LOCAL find$
      find$ = FN_getdlgitemtext(FindDlg%, 103)
      IF find$ = "" ENDPROC
      IF NOT FNsearch(find$, Buffer$(), Indent%(), nLines%, FindFlags%, \
      \               AnchorX%, AnchorY%, CaretX%, CaretY%) THEN
        PROCmessagebox("SDLIDE", "String not found", MB_ICONINFORMATION)
        CaretX% = 0 : CaretY% = 0 : AnchorX% = 0 : AnchorY% = 0
      ENDIF
      Refresh% = TRUE
      ENDPROC
      
      REM Edit... Go To
      DEF PROCgotoline(nl%)
      LOCAL L%, R%
      
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      
      OSCLI "FONT " + GUIFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      
      PROC_registerdlgcallback(GotoDlg%, FNdlgcb())
      PROC_setdlgitemtext(GotoDlg%, 101, STR$(CaretY%))
      R% = FN_showdialogex(GotoDlg%, &80000000, &80000000, Darkmode%)
      *REFRESH ON
      
      IF R% = 1 THEN
        L% = VAL(FN_getdlgitemtext(GotoDlg%, 101))
        IF L% < nl% THEN
          PROCsavejump(GoBack%(), ScrollV%, BackLevel%)
          CaretX% = 0 : CaretY% = L% : AnchorX% = 0 : AnchorY% = L%
        ENDIF
      ENDIF
      
      PROC_closedialog(GotoDlg%)
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      
      Refresh% = TRUE : REM To reset caret
      ENDPROC
      
      DEF __Utilities_Menu__
      
      REM Utilities... Compile
      DEF PROCcompile
      LOCAL bbcfile$, dir$, exe$, ch%
      dir$ = FNpath(CurrentFile$)
      exe$ = FNnoext(FNnopath(CurrentFile$))
      IF dir$ = "" dir$ = FNgetcwd + RIGHT$(@lib$)
      IF BB4W% THEN
        bbcfile$ = dir$ + "compiler.tmp.bbc"
        exe$ += ".exe, encrypt"
      ELSE
        bbcfile$ = @tmp$ + "compiler.tmp.bbc"
      ENDIF
      ch% = OPENOUT(bbcfile$)
      IF ch% = 0 PROCmessagebox("SDLIDE", "Couldn't create " + bbcfile$, &30) : ENDPROC
      BPUT #ch%, FNtokenise("REM!Exefile " + dir$ + "exe" + RIGHT$(@tmp$) + exe$);
      BPUT #ch%, SUM(Buffer$());
      BPUT #ch%, CHR$0+CHR$&FF+CHR$&FF;
      CLOSE #ch%
      IF BB4W% THEN
        SYS "WinExec", """" + @lib$ + "../bbcwin6.exe"" -c """ + bbcfile$ + """", 0
        WAIT 100 : OSCLI "del """ + bbcfile$ + """"
      ELSE
        PROCexecute(@dir$ + "compiler.bbc", FNdark) : REM Not -hidden because of error box
      ENDIF
      ENDPROC
      
      REM Utilities... Renumber
      DEF PROCrenumber(f$(), nl%) IF nl% = 0 ENDPROC
      LOCAL a$, c&, l&, h&, I%, L%, N%, R%, t%%, first%, incr%, remove%, lino%(), flag&()
      DIM lino%(nl%-1), flag&(nl%-1)
      
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      
      OSCLI "FONT " + GUIFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      
      PROC_registerdlgcallback(RenumDlg%, FNdlgcb())
      REPEAT
        R% = FN_showdialogex(RenumDlg%, &80000000, &80000000, Darkmode%)
        first% = VAL(FN_getdlgitemtext(RenumDlg%, 103))
        incr%  = VAL(FN_getdlgitemtext(RenumDlg%, 104))
        remove% = FN_isdlgitemchecked(RenumDlg%, 105)
        
        IF R% = 1 IF first% + (nl%-1) * incr% > 65535 THEN
          PROCmessagebox("SDLIDE", "These values would result in a " + \
          \              "line number greater than 65535", MB_ICONWARNING)
          *REFRESH OFF
          PROC_closedialog(RenumDlg%)
          R% = 0
        ENDIF
      UNTIL R%
      *REFRESH ON
      PROC_closedialog(RenumDlg%)
      
      IF R% = 1 THEN
        PROCundosave(f$(), BreakPt&(), nLines%, UndoLevel%, RedoLevel%, CaretX%, CaretY%)
        
        FOR L% = 0 TO nl%-1
          lino%(L%) = !(PTR(f$(L%)) + 1) AND &FFFF
        NEXT
        
        FOR L% = 0 TO nl%-1
          a$ = f$(L%)
          R% = 3
          REPEAT
            R% = FNinstrq(a$, CHR$&8D, R%+1)
            IF R% THEN
              t%% = PTR(a$) + R% - 1
              c& = t%%?1
              l& = ((c& << 2) AND &C0) EOR t%%?2
              h& = ((c& << 4) AND &C0) EOR t%%?3
              N% = l& + 256*h&
              FOR I% = 0 TO nl%-1
                IF N% = lino%(I%) EXIT FOR
              NEXT
              IF I% < nl% THEN
                flag&(I%) = 1
                N% = first% + I% * incr%
                l& = N% MOD 256
                h& = N% DIV 256
                t%%?1 = &54 EOR (((h& AND &C0) >> 4) OR ((l& AND &C0) >> 2))
                t%%?2 = &40 OR (l& AND &3F)
                t%%?3 = &40 OR (h& AND &3F)
              ELSE
                PROCmessagebox("SDLIDE", "No line " + STR$N% + \
                \              " referenced in (new) line " + STR$(first% + L%*i%), \
                \              MB_ICONWARNING)
              ENDIF
            ENDIF
          UNTIL R% = 0
          f$(L%) = a$
        NEXT L%
        
        FOR L% = 0 TO nl%-1
          a$ = f$(L%)
          IF remove% IF flag&(L%) = 0 THEN
            MID$(a$,2,2) = CHR$0+CHR$0
          ELSE
            N% = first% + L% * incr%
            MID$(a$,2,2) = CHR$(N% MOD 256) + CHR$(N% DIV 256)
          ENDIF
          f$(L%) = a$
        NEXT
        Changed% = TRUE
      ENDIF
      
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      
      Refresh% = TRUE : REM To reset caret
      ENDPROC
      
      DEF FNdlgcb(D%, K%) : LOCAL R%
      R% = FN_getdlgfocus(D%) : IF R% > 9 R% = 1
      IF K% = 13 THEN = R%
      IF K% = 27 THEN = 2
      = 0
      
      REM Utilities... List FNs/PROCs
      DEF PROClistdefs(f$(), nl%)
      LOCAL A%,C%,I%,N%,T%,a$,d$(),l%()
      FOR I% = 0 TO nl%-1
        T% = ASCMID$(f$(I%),4)
        IF T%=&DD N% += 1
        IF IncludeON% IF T%=&EE THEN
          C% = 4 : REPEAT C% += 1 : UNTIL ASCMID$(f$(I%),C%) <> 32
          IF ASCMID$(f$(I%),C%) < 13 OR ASCMID$(f$(I%),C%) > 127 N% += 1
        ENDIF
        IF IncludeLab% IF T%=&28 N% += 1
      NEXT
      IF N% = 0 THEN ENDPROC
      DIM d$(N%), l%(N%)
      N% = 0
      FOR I% = 0 TO nl%-1
        T% = ASCMID$(f$(I%),4)
        IF T%=&DD THEN
          A% = 0
          a$ = MID$(FNstrip(FNformat(f$(I%),A%)),7)
          a$ = MID$(a$,4)
          A% = INSTR(a$,"(") : IF A% a$ = LEFT$(a$,A%) + ")"
          A% = INSTR(a$,":") : IF A% a$ = LEFT$(a$,A%-1)
          N% += 1
          d$(N%) = FN_trim(a$)
          l%(N%) = I%
        ENDIF
        IF IncludeON% IF T%=&EE THEN
          C% = 4 : REPEAT C% += 1 : UNTIL ASCMID$(f$(I%),C%) <> 32
          IF ASCMID$(f$(I%),C%) < 13 OR ASCMID$(f$(I%),C%) > 127 THEN
            A% = 0
            a$ = MID$(FNstrip(FNformat(f$(I%),A%)),7)
            C% -= 3 : REPEAT C% += 1 : UNTIL ASCMID$(a$,C%) < 64
            IF INSTR(f$(I%),CHR$&EA,4) THEN
              REPEAT C% += 1 : UNTIL ASCMID$(a$,C%) > 32
              REPEAT C% += 1 : UNTIL ASCMID$(a$,C%) < 64
            ENDIF
            N% += 1
            d$(N%) = FN_trim(LEFT$(a$,C%))
            l%(N%) = I%
          ENDIF
        ENDIF
        IF IncludeLab% IF T%=&28 THEN
          A% = 0
          a$ = MID$(FNstrip(FNformat(f$(I%),A%)),7)
          C% = INSTR(a$, ")")
          N% += 1
          d$(N%) = FN_trim(LEFT$(a$,C%))
          l%(N%) = I%
        ENDIF
      NEXT
      IF SortList% C% = N% : CALL Sort%%, d$(1), l%(1)
      I% = FNcombo(d$(), N%, ComboBox.l%, ComboBox.t% + 2, ComboBox.r%-ComboBox.l%+2)
      *REFRESH ON
      IF I% THEN
        PROCsavejump(GoBack%(), ScrollV%, BackLevel%)
        ScrollV% = l%(I%) * @vdu%!220 * 2
      ENDIF
      ENDPROC
      
      REM Utilities... Addins
      DEF PROCrunaddin(addin$)
      LOCAL bbcfile$, ch%
      IF addin$ = "" ENDPROC
      bbcfile$ = @tmp$ + "program.tmp.bbc"
      ch% = OPENOUT(bbcfile$)
      BPUT #ch%, SUM(Buffer$());
      BPUT #ch%, CHR$0+CHR$&FF+CHR$&FF;
      CLOSE #ch%
      PROCexecute(addin$, "-hidden " + FNdark + " -file " + CurrentFile$)
      ENDPROC
      
      DEF __Options_Menu__
      
      REM Options... Syntax Colouring
      DEF PROCtogglecolouring
      LOCAL C%, I%
      Colouring% EOR= TRUE
      IF Colouring% THEN
        FOR I% = 1 TO 6
          C% = Colours%(I%-1)
          COLOR I%, (C% AND &FF0000) >> 16, (C% AND &FF00) >> 8, C% AND &FF
        NEXT
      ELSE
        FOR I% = 1 TO 6
          IF Darkmode% COLOR I%, &FF, &FF, &FF ELSE COLOR I%, 0, 0, 0
        NEXT
      ENDIF
      Refresh% = TRUE
      ENDPROC
      
      REM Options... Lowercase Keywords
      DEF PROCtogglelowercase
      Lowercase% EOR= TRUE
      IF Lowercase% Abbrev% = FALSE
      Refresh% = TRUE
      ENDPROC
      
      REM Options... Indentation
      DEF PROCtoggleindentation
      Indentation% EOR= TRUE
      Refresh% = TRUE
      ENDPROC
      
      REM Options... Keyword abbreviations
      DEF PROCtoggleabbrev
      Abbrev% EOR= TRUE
      Refresh% = TRUE
      ENDPROC
      
      REM Options... Unicode Support
      DEF PROCtoggleunicode
      Unicode% EOR= TRUE
      Refresh% = TRUE
      ENDPROC
      
      REM Options... Set Font
      DEF PROCsetfont
      LOCAL F%, H%, I%, N%, R%, W%, X%, Y%, face$, style$, size$
      PRIVATE face$(), style$(), size$()
      DIM face$(1000), style$(4), size$(20)
      style$() = "", "Regular", "Italic", "Bold", "Bold Italic"
      size$() = "", "8", "9", "10", "11", "12", "13", "14", "16", "18", "20", "22", \
      \         "24", "28", "32", "36", "40", "48", "56", "64", "72"
      face$() = "", "Arial,ttf", "Consolas.ttf", "Courier New.ttf", "Lucida Console.ttf"
      
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      
      OSCLI "FONT " + GUIFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      
      PROC_setlistboxarray(FontDlg%, 103, style$(), 4)
      PROC_setlistboxarray(FontDlg%, 105, size$(), 20)
      
      I% = INSTR(EditFont$, ",")
      IF I% THEN
        face$ = LEFT$(EditFont$, I% - 1)
        PROC_setlistboxselect(FontDlg%, 105, VALMID$(EditFont$, I%+1) - 7)
        I% = INSTR(EditFont$, ",", I% + 1)
        IF I% THEN
          IF INSTR(EditFont$, "I", I% + 1) N% OR= 1
          IF INSTR(EditFont$, "B", I% + 1) N% OR= 2
        ENDIF
        PROC_setlistboxselect(FontDlg%, 103, N% + 1)
        I% = FNinstrr(face$, "/", 0)
        IF I% = 0 I% = FNinstrr(face$, "\", 0)
        IF I% face$ = MID$(LEFT$(face$), I% + 1)
      ENDIF
      
      IF BB4W% N% = 4 ELSE N% = FNdirscan(face$(), "dir """ + @lib$ + "*.*""", "*.ttf;*.otf", "", "")
      FOR I% = 1 TO N%
        IF BB4W% face$(I%) = LEFT$(face$(I%), LEN(face$(I%)) - 4)
        IF face$(I%) = face$ F% = I%
      NEXT
      IF N% = 0 face$(1) = face$ : N% = 1 : F% = 1
      PROC_setlistboxarray(FontDlg%, 101, face$(), N%)
      PROC_setlistboxselect(FontDlg%, 101, F%)
      PROC_registerdlgcallback(FontDlg%, FNdlgcb())
      
      X% = &80000000 : Y% = &80000000
      REPEAT
        OFF
        R% = FN_showdialogex(FontDlg%, X%, Y%, Darkmode%)
        PROC_getdlgrect(FontDlg%, X%, Y%, W%, H%)
        face$ = FN_getdlgitemtext(FontDlg%, 101)
        style$ = FN_getdlgitemtext(FontDlg%, 103)
        size$ = FN_getdlgitemtext(FontDlg%, 105)
        style$ = LEFT$("B",INSTR(style$,"B")) + LEFT$("I",INSTR(style$,"I"))
        IF R% = 3 THEN
          *REFRESH OFF
          PROC_closedialog(FontDlg%)
          IF BB4W% THEN
            OSCLI "FONT " + face$ + "," + size$ + "," + style$
          ELSE
            OSCLI "FONT """ + @lib$ + face$ + """," + size$ + "," + style$
          ENDIF
          PROCrefresh(ScrollH%, ScrollV%, CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
          OSCLI "FONT " + GUIFont$
          VDU 23,0,10,0,0;0;0; : REM Set start line
          VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
          VDU 23,0,18,2,0;0;0; : REM Set cursor width
        ENDIF
      UNTIL R% = 1 OR R% = 2
      IF R% = 1 THEN
        IF BB4W% THEN
          EditFont$ = face$ + "," + size$ + "," + style$
        ELSE
          EditFont$ = """" + @lib$ + face$ + """," + size$ + "," + style$
        ENDIF
      ENDIF
      *REFRESH ON
      Refresh% = TRUE
      PROC_closedialog(FontDlg%)
      
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      ENDPROC
      
      REM Options... Set Colours
      DEF PROCsetcolours
      LOCAL H%, I%, N%, R%, W%, X%, Y%
      
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      
      OSCLI "FONT " + GUIFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      
      PROC_checkdlgitem(ColorDlg%, 101, 0)
      PROC_checkdlgitem(ColorDlg%, 102, 0)
      PROC_checkdlgitem(ColorDlg%, 103, 0)
      PROC_checkdlgitem(ColorDlg%, 104, 0)
      PROC_checkdlgitem(ColorDlg%, 105, 0)
      PROC_checkdlgitem(ColorDlg%, 106, 1)
      PROC_registerdlgcallback(ColorDlg%, FNclrcb())
      
      X% = &80000000 : Y% = &80000000
      REPEAT
        OFF
        R% = FN_showdialogex(ColorDlg%, X%, Y%, Darkmode%)
        PROC_getdlgrect(ColorDlg%, X%, Y%, W%, H%)
        IF R% = 1 OR R% = 3 THEN
          FOR I% = 101 TO 106
            IF FN_isdlgitemchecked(ColorDlg%, I%) EXIT FOR
          NEXT
          N% = Palette%(SelCol% DIV 10, SelCol% MOD 10)
          Colours%(I% - 101) = N%
          COLOR I% - 100, N% >> 16, (N% AND &FF00) >> 8, N% AND &FF
        ENDIF
        IF R% = 3 THEN
          PROC_setdlgitemtext(ColorDlg%, 2, "Close")
          *REFRESH OFF
          PROC_closedialog(ColorDlg%)
          OSCLI "FONT " + EditFont$
          PROCrefresh(ScrollH%, ScrollV%, CaretX%, CaretY%, AnchorX%, AnchorY%, nLines%)
          OSCLI "FONT " + GUIFont$
          VDU 23,0,10,0,0;0;0; : REM Set start line
          VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
          VDU 23,0,18,2,0;0;0; : REM Set cursor width
        ENDIF
      UNTIL R% = 1 OR R% = 2
      *REFRESH ON
      Refresh% = TRUE
      PROC_closedialog(ColorDlg%)
      
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      ENDPROC
      
      REM Options... Dark Mode
      DEF PROCtoggledarkmode
      Darkmode% EOR= TRUE
      PROCsetpalette
      Resized% = TRUE
      ENDPROC
      
      DEF FNclrcb(D%, K%)
      LOCAL C%, F%, I%, P%, R%
      PRIVATE S%
      F% = FN_getdlgfocus(D%)
      IF F% >= 200 SelCol% = F% - 200
      IF F% > 9 F% = 1
      FOR I% = 101 TO 106
        IF FN_isdlgitemchecked(D%, I%) EXIT FOR
      NEXT
      IF S% <> I% THEN
        S% = I%
        P% = Colours%(S% - 101)
        FOR R% = 0 TO 5
          FOR C% = 0 TO 7
            IF Palette%(R%, C%) = P% PROC_setdlgfocus(D%, 200 + R%*10 + C%)
          NEXT
        NEXT R%
      ENDIF
      R% = SelCol% DIV 10
      C% = SelCol% MOD 10
      CASE K% OF
        WHEN 13: = F%
        WHEN 27: = 2
        WHEN 136: C% = (C% + 7) MOD 8
        WHEN 137: C% = (C% + 1) MOD 8
        WHEN 138: R% = (R% + 1) MOD 6
        WHEN 139: R% = (R% + 5) MOD 6
        OTHERWISE: = 0
      ENDCASE
      PROC_setdlgfocus(D%, 200 + R%*10 + C%)
      = 0
      
      DEF __Run_Menu__
      
      REM Run... Run Program
      REM Run... Debug Program
      REM Run... Profile Program
      REM Run... Immediate
      DEF PROCimmediate : LOCAL debug%, imm% : imm% = 1
      DEF PROCprofile : LOCAL debug%, imm% : debug% = 1
      DEF PROCdebug : LOCAL debug%, imm% : debug% = TRUE
      DEF PROCrun : LOCAL debug%, imm%
      LOCAL breakpt$, bbcfile$, dir$, ch%, I%
      dir$ = FNpath(CurrentFile$)
      IF dir$ = "" dir$ = FNgetcwd + RIGHT$(@lib$)
      bbcfile$ = @tmp$ + FNnopath(CurrentFile$) + ".tmp"
      ch% = OPENOUT(bbcfile$)
      IF ch% = 0 PROCmessagebox("SDLIDE", "Couldn't create " + bbcfile$, &30) : ENDPROC
      IF debug% THEN
        IF debug% > 0 THEN
          BPUT #ch%, FNtokenise("P% = TRUE : CALL @lib$+""sdldebug""");
        ELSE
          BPUT #ch%, FNtokenise("P% = FALSE : CALL @lib$+""sdldebug""");
        ENDIF
      ENDIF
      BPUT #ch%, FNtokenise("dir$ = """ + dir$ + """");
      BPUT #ch%, FNtokenise("$PTR(@dir$) = dir$ : !(^@dir$+4) = LEN(dir$)");
      BPUT #ch%, FNtokenise("OSCLI ""cd """""" + dir$ + """"""""");
      IF imm% THEN
        BPUT #ch%, FNtokenise("PAGE = PAGE + &200 : CLEAR : END");
      ELSE
        BPUT #ch%, FNtokenise("PAGE = PAGE + &200 : CLEAR : RUN");
      ENDIF
      BPUT #ch%, FNtokenise("REM" + STRING$((502 - PTR#ch%) DIV 2, "x"));
      BPUT #ch%, FNtokenise("REM" + STRING$(507 - PTR#ch%, "x"));
      
      IF debug% THEN
        breakpt$ = CHR$6 + CHR$0 + CHR$0 + CHR$&FC + CHR$&88
        FOR I% = 0 TO DIM(Buffer$(),1)
          BBCPtr%(I%) = PTR#ch%
          BBCTok&(I%) = ASCMID$(Buffer$(I%),4)
          BPUT #ch%, Buffer$(I%);
          IF debug%<0 IF BreakPt&(I%) PRINT #ch%, breakpt$
        NEXT
      ELSE
        BPUT #ch%, SUM(Buffer$());
      ENDIF
      BPUT #ch%, CHR$0+CHR$&FF+CHR$&FF;
      CLOSE #ch%
      PROCexecute(bbcfile$, "")
      ENDPROC
      
      REM Run... Stop
      DEF PROCstop
      PROCdebugcmd(TRUE, FALSE)
      ENDPROC
      
      REM Run... Pause
      DEF PROCpause
      LOCAL paused%
      paused% = TBpressed&(16) <> 0
      IF paused% THEN
        PROCdebugcmd(0, &10000000)
      ELSE
        PROCdebugcmd(1, &10000000)
      ENDIF
      ENDPROC
      
      REM Run... Step Into
      DEF PROCstepinto
      PROCdebugcmd(1, &10000000)
      ENDPROC
      
      REM Run... Step Over
      DEF PROCstepover
      LOCAL F%, I%, curlin%, lin1%, lin2%
      FOR I% = 1 TO 10
        F% = OPENIN(@tmp$ + "sdldebug.dat")
        IF F% EXIT FOR
        WAIT RND(3)
      NEXT
      IF F% = 0 ENDPROC
      curlin% = BGET#F% OR (BGET#F% << 8) OR (BGET#F% << 16) OR (BGET#F% << 24)
      CLOSE #F%
      lin1% = FNchop(BBCPtr%(), curlin%) + 1 : lin2% = lin1%
      IF lin1% > &FFFF ENDPROC
      REPEAT lin2% += 1 UNTIL INSTR(Skip$, CHR$BBCTok&(lin2%)) = 0
      PROCdebugcmd(BBCPtr%(lin1%), BBCPtr%(lin2%))
      ENDPROC
      
      REM Run... Run to Cursor
      DEF PROCrununtil
      LOCAL lin2%
      PROCdebug
      lin2% = CaretY%
      REPEAT lin2% += 1 UNTIL INSTR(Skip$, CHR$BBCTok&(lin2%)) = 0
      PROCdebugcmd(BBCPtr%(CaretY%), BBCPtr%(lin2%))
      ENDPROC
      
      DEF __Help_Menu__
      
      REM Help... Help Topics
      DEF PROCtopics
      IF BB4W% THEN
        PROCopenurl("https://www.bbcbasic.co.uk/bbcwin/manual/index.html")
      ELSE
        PROCopenurl("https://www.bbcbasic.co.uk/bbcsdl/manual/index.html")
      ENDIF
      ENDPROC
      
      REM Help... Tutorial
      DEF PROCtutorial
      IF BB4W% THEN
        PROCopenurl("https://www.bbcbasic.co.uk/bbcwin/tutorial/index.html")
      ELSE
        PROCopenurl("https://www.bbcbasic.co.uk/bbcsdl/tutorial/index.html")
      ENDIF
      ENDPROC
      
      REM Help... Website
      DEF PROCwebsite
      IF BB4W% THEN
        PROCopenurl("https://www.bbcbasic.co.uk/bbcwin/index.html")
      ELSE
        PROCopenurl("https://www.bbcbasic.co.uk/bbcsdl/index.html")
      ENDIF
      ENDPROC
      
      REM Help... Email
      DEF PROCemail
      PROCopenurl("mailto:info@rtrussell.co.uk?subject=BBC%20BASIC%20for%20SDL%202.0")
      ENDPROC
      
      REM Help... Discussion Group
      DEF PROCdiscuss
      PROCopenurl("https://groups.io/g/bb4w/")
      ENDPROC
      
      REM Help... Message Board
      DEF PROCforum
      PROCopenurl("https://www.bbcbasic.co.uk/forum/")
      ENDPROC
      
      REM Help... Wiki
      DEF PROCwiki
      PROCopenurl("https://www.bbcbasic.co.uk/wiki/")
      ENDPROC
      
      REM Help... About BBC BASIC
      DEF PROCabout
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      LOCAL R%
      OSCLI "FONT " + GUIFont$
      PROC_registerdlgcallback(AboutBox%, FNdlgcb())
      R% = FN_showdialog(AboutBox%, &80000000, &80000000)
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      Refresh% = TRUE : REM To reset caret
      ENDPROC
      
      DEF  __Context_Menu__
      
      REM Right-click menu:
      DEF PROCcontextmenu(X%, Y%)
      LOCAL A%, C%, I%, J%, N%, R%, S%, U%, fnproc$, menu$(), menu%()
      A% = FNisallrems(Buffer$(), CaretY%, AnchorY%)
      C% = FNhascliptext
      J% = BackLevel% <> 0
      R% = CaretY% <> AnchorY%
      S% = R% OR CaretX% <> AnchorX%
      fnproc$ = FNisfnproc(Buffer$(), Indent%(), X%, Y%, nLines%, I%)
      U% = fnproc$ <> ""
      N% = - S%*2 - R% - C% - J% - U%
      IF N% = 0 ENDPROC
      DIM menu$(N% - 1), menu%(N% - 1)
      N% = 0
      IF S% menu$() = "Cut", "Copy" : menu%() = 322, 323 : N% += 2
      IF C% menu$(N%) = "Paste"     : menu%(N%) = 324    : N% += 1
      IF R% THEN
        IF A% THEN
          menu$(N%) = "Remove REMs" : menu%(N%) = 371    : N% += 1
        ELSE
          menu$(N%) = "Add REMs"    : menu%(N%) = 370    : N% += 1
        ENDIF
      ENDIF
      IF J% menu$(N%) = "Go back"   : menu%(N%) = 372    : N% += 1
      IF U% menu$(N%) = "Jump to " + fnproc$ : menu%(N%) = 373 : N% += 1
      Click%() = FNmenu(IDPOPUP, menu$(), menu%(), X%, Y%), I% * @vdu%!220 * 2, 0
      ENDPROC
      
      REM Add REMs to selected block:
      DEF PROCaddrems(f$(), i%(), cy%, ay%, nl%)
      LOCAL a$,I%,M%,T%,Y%
      IF ay% = cy% THEN = FALSE
      IF ay% < cy% SWAP ay%,cy%
      I% = i%(cy%)
      FOR Y% = cy% TO ay%-1
        T% = 0
        a$ = FNstrip(FNformat(f$(Y%),T%))
        a$ = LEFT$(a$,6) + "REM " + MID$(a$,7)
        f$(Y%) = FNtokenise(a$)
        i%(Y%) = I%
        PROCindent(f$(Y%),I%,M%)
      NEXT
      I% -= i%(Y%)
      IF I%=0 ENDPROC
      WHILE Y% <= nl%
        i%(Y%) += I%
        Y% += 1
      ENDWHILE
      ENDPROC
      
      REM Remove REMs from selected block:
      DEF PROCremrems(f$(), i%(), cy%, ay%, nl%)
      LOCAL a$,I%,M%,T%,Y%
      IF ay% = cy% THEN = FALSE
      IF ay% < cy% SWAP ay%,cy%
      I% = i%(cy%)
      FOR Y% = cy% TO ay%-1
        T% = 0
        a$ = FNstrip(FNformat(f$(Y%),T%))
        a$ = LEFT$(a$,6) + MID$(a$,10)
        f$(Y%) = FNtokenise(a$)
        i%(Y%) = I%
        PROCindent(f$(Y%),I%,M%)
      NEXT
      I% -= i%(Y%)
      IF I%=0 ENDPROC
      WHILE Y% < nl%
        i%(Y%) += I%
        Y% += 1
      ENDWHILE
      ENDPROC
      
      DEF PROCgoback
      IF BackLevel% = 0 ENDPROC
      BackLevel% -= 1
      ScrollV% = GoBack%(BackLevel%)
      Refresh% = TRUE
      ENDPROC
      
      DEF PROCjumpto(L%)
      IF L% = -1 ENDPROC
      PROCsavejump(GoBack%(), ScrollV%, BackLevel%)
      ScrollV% = L%
      Refresh% = TRUE
      ENDPROC
      
      REM Hover toolbar or keyword tooltip:
      DEF PROCtooltip(X%, Y%)
      LOCAL H%, I%, P%, V%, W%, Z%, f$, k$, t$
      IF Y% > EditRect.t% THEN
        V% = X% : W% = EditRect.t% + BUTTONHEIGHT + 10
        IF Y% > W% ENDPROC
        I% = FNchop(ToolPos%(), X%)
        IF I% <= DIM(ToolTip$(),1) t$ = ToolTip$(I%) ELSE ENDPROC
        t$ = " " + t$ + " " : P% = WIDTH(t$) : H% = @char.y% * 3
        IF V% + P% > @size.x% * 2 V% = @size.x% * 2 - P%
        IF W% + H% > @size.y% * 2 W% = @size.y% * 2 - H%
      ELSE
        V% = X% : W% = Y% + @char.y%
        PROCpointtochar(X%, Y%)
        I% = Indent%(Y%)
        f$ = FNformat(Buffer$(Y%), I%)
        k$ = CHR$18 + CHR$0 + CHR$COL_KEYWD
        I% = INSTR(f$, CHR$18 + CHR$0 + CHR$COL_DEF)
        REPEAT
          P% = I%
          I% = INSTR(f$, k$, I% + 1)
        UNTIL I% = 0 OR LENFNstrip(LEFT$(f$,I%)) > X%
        IF P% = 0 ENDPROC
        I% = INSTR(f$, CHR$18 + CHR$0, P%+1) : IF I% = 0 I% = LEN(f$) + 1
        IF X% > LENFNstrip(LEFT$(f$,I%)) ENDPROC
        k$ = MID$(f$, I% + 3, 1)
        f$ = FN_trim(FN_upper(MID$(f$,P% + 3,I% - P% - 3)))
        IF k$ = "#" OR k$ = "=" OR k$ = "~" OR k$ = "$" f$ += k$
        I% = FNchops(KeywTip$(), f$ + " ") : H% = @char.y%
        WHILE ASCKeywTip$(I%) = 9 : I% -= 1 : ENDWHILE : P% = 0
        REPEAT f$ = KeywTip$(I%)
          REPEAT Z% = INSTR(f$, CHR$9 + CHR$9) : IF Z% MID$(f$, Z%, 1) = CHR$0
          UNTIL Z% = 0
          REPEAT Z% = INSTR(f$, CHR$9, 2) : IF Z% MID$(f$, Z%, 1) = ":"
          UNTIL Z% = 0
          IF ASCf$ = 9 f$ = CHR$&D + CHR$&A + STRING$(INSTR(t$, ":"), " ") + MID$(f$, 2)
          IF WIDTH(f$) > P% P% = WIDTH(f$)
          WHILE P% > @size.x% * 2 f$ = LEFT$(f$) : P% = WIDTH(f$) : ENDWHILE
          t$ += " " + f$ : H% += @char.y% * 2 : I% += 1
        UNTIL ASCKeywTip$(I%) <> 9 : P% += 20 + WIDTH(" ")
        IF V% + P% > EditRect.r% V% = EditRect.r% - P% : IF V% < 0 V% = 0
        IF W% + H% > EditRect.t% W% = EditRect.t% - H% : IF W% < 0 W% = 0
      ENDIF
      OSCLI "GSAVE """ + @tmp$ + "tooltip" + Session$ + """" + STR$V% + "," + STR$W% + \
      \                                                  "," + STR$P% + "," + STR$(H%+1)
      VDU 24, V%; W%; V% + P% - 2; W% + H% - 2; 5
      GCOL 128 + COL_GUIBKGD : GCOL 0 : CLG : RECTANGLE V%, W%, P% - 2, H% - 2
      VDU 30 : MOVE BY 0, -@char.y% DIV 2 : PRINT t$;
      VDU 24, 0; 0; @size.x%*2-2; @size.y%*2-2; 4
      MOUSE H%, I%, P% : REPEAT MOUSE X%, Y%, P% : Z% = INKEY(1)
      UNTIL X% <> H% OR Y% <> I% OR Z% <> -1 OR INKEY(-10) OR INKEY(-12)
      IF Z% <> -1 Click%(0) = Z%
      OSCLI "DISPLAY """ + @tmp$ + "tooltip" + Session$ + """" + STR$V% + "," + STR$W%
      ENDPROC
      
      REM!Eject --------------------------------------------------------------------------
      DEF __GUI_Widgets__
      
      DEF FNmenu(D%, m$(), m%(), X%, Y%)
      LOCAL B%, H%, I%, K%, L%, N%, O%, P%, Q%, R%, S%, T%, U%, W%, Z%, a$, click%
      ON TIME LOCAL OFF
      ON MOUSE LOCAL click% = TRUE : RETURN
      PROCcursor(0)
      OSCLI "FONT " + GUIFont$
      
      FOR I% = 0 TO DIM(m$(),1)
        a$ = "       " + m$(I%)
        T% = INSTR(a$,"&")
        IF T% a$ = LEFT$(a$,T%-1) + MID$(a$,T%+1)
        IF m%(I%) = 0 H% += 20 ELSE H% += @vdu%!220 * 2
        T% = INSTR(a$, CHR$9)
        IF T% THEN
          N% = FN_stringwidth(LEFT$(a$,T%-1))
          IF N% > L% L% = N%
          N% = FN_stringwidth(MID$(a$,T%+1)) + 20
          IF N% > R% R% = N%
        ELSE
          N% = FN_stringwidth(a$)
          IF N% > L% L% = N%
        ENDIF
      NEXT
      H% += 10
      L% += 20
      W% = L% + R%
      IF Y% - H% < STATUSBARHEIGHT Y% = STATUSBARHEIGHT + H%
      OSCLI "GSAVE """ + @tmp$ + "bbc" + Session$ + ".tmp.bmp" + """ " + STR$X% + "," + STR$(Y%-H%) + \
      \     "," + STR$(W%+2) + "," + STR$(H%+2)
      
      GCOL COL_BORDERS
      RECTANGLE X%, Y%, W%, -H%
      
      S% = -1
      O% = -2
      Z% = TIME + 50
      MOUSE P%, Q%, B%
      REPEAT UNTIL INKEY(0) = -1
      REPEAT
        *REFRESH OFF
        GCOL 128 + COL_GUIBKGD
        VDU 24,X%+2;Y%-H%+2;X%+W%-2;Y%-2;5
        VDU 16,30,23,16,64|
        FOR I% = 0 TO DIM(m$(),1)
          GCOL 128 + COL_BORDERS
          a$ = "       " + m$(I%)
          U% = INSTR(a$,"&")
          IF U% a$ = LEFT$(a$,U%-1) + MID$(a$,U%+1)
          IF m%(I%) = 0 THEN
            PLOT 0,0,-10 : PLOT 3,W%,0 : PLOT 0,-W%,-10
          ELSE
            T% = INSTR(a$,CHR$9)
            IF T% THEN
              PRINT LEFT$(a$,T%-1);
              VDU 13 : PLOT 0,L%,0 : PRINT MID$(a$,T%+1)
            ELSE
              PRINT a$
            ENDIF
            IF U% THEN
              T% = FN_stringwidth(LEFT$(a$,U%-1))
              U% = FN_stringwidth(MID$(a$,U%,1)) - 2
              PLOT 0,T%,4
              PLOT 1,U%,0
              PLOT 0,-(T%+U%),-4
            ENDIF
            IF m%(I%) AND &2000 THEN
              N% = @vdu%!220 DIV 2
              VDU 23,23,3|
              PLOT 0,N%*2,N%*2
              PLOT 9,N%,-N%
              VDU 23,23,2|
              PLOT 9,N%,N%*2 + 4
              PLOT 0,-N%*4,-N%*3 - 4
              VDU 23,23,1|
            ENDIF
            IF I% = S% THEN
              GCOL 2,128 + COL_HILITEAND
              PLOT 99,W%,@vdu%!220*2
              GCOL 1,128 + COL_HILITEOR
              PLOT 99,-W%,-@vdu%!220*2
              GCOL 0,128 + COL_SELECT
              PLOT 3,0,@vdu%!220*2 : PLOT 3,W%,0
              PLOT 3,0,-@vdu%!220*2 : PLOT 3,-W%,0
            ENDIF
            IF m%(I%) AND &1000 THEN
              IF Darkmode% GCOL 2,128 + COL_DISABLED ELSE GCOL 1,128 + COL_DISABLED
              PLOT 99,W%,@vdu%!220*2
              PLOT 0,-W%,-@vdu%!220*2
            ENDIF
          ENDIF
        NEXT
        *REFRESH
        
        N% = DIM(m%(),1) + 1
        K% = INKEY(4)
        CASE K% OF
          WHEN 13:  IF S% >= 0 IF (m%(S%) AND &1000) = 0 S% = m%(S%) AND &FFF : EXIT REPEAT
          WHEN 27:  S% = 0 : EXIT REPEAT
          WHEN 136: S% = -136 : EXIT REPEAT
          WHEN 137: S% = -137 : EXIT REPEAT
          WHEN 138: REPEAT S% = (S% + N% + 1) MOD N% : UNTIL m%(S%)
          WHEN 139: REPEAT S% = (S% + N% + (S%>=0)) MOD N% : UNTIL m%(S%)
          OTHERWISE:
            FOR I% = 0 TO N% - 1
              a$ = m$(I%)
              U% = INSTR(a$,"&")
              IF U% IF (m%(I%) AND &1000) = 0 THEN
                T% = ASCMID$(a$, U%+1)
                IF (K% AND &5F) = (T% AND &5F)             S% = m%(I%) AND &FFF : EXIT REPEAT
                IF INKEY(-InKey&(T% AND &3F)) IF TIME > Z% S% = m%(I%) AND &FFF : EXIT REPEAT
              ENDIF
            NEXT
        ENDCASE
        
        MOUSE I%, T%, B%
        IF I%<>P% OR T%<>Q% THEN
          P% = I% : Q% = T%
          IF Q% > Y% THEN
            N% = FNhotspot(P%, Q%)
            IF N% >= 0 IF N% < D% S% = -136 : EXIT REPEAT
            IF N% >= 0 IF N% > D% S% = -137 : EXIT REPEAT
          ENDIF
          IF P% > X% IF P% < X%+W% IF Q% < Y% IF Q% > Y%-H% THEN
            T% = Y% : N% = 0
            FOR I% = 0 TO DIM(m$(),1)
              IF Q% > T% - 2*@vdu%!220 IF Q% < T% S% = I%
              IF m%(I%) = 0 T% -= 20 ELSE T% -= 2*@vdu%!220 : N% += 1
            NEXT
          ELSE
            S% = -1
          ENDIF
        ENDIF
        
        IF click% THEN
          click% = FALSE
          IF S% >= 0 THEN
            IF (m%(S%) AND &1000) = 0 S% = m%(S%) AND &FFF : EXIT REPEAT
          ELSE
            S% = 0
            EXIT REPEAT
          ENDIF
        ENDIF
        
        IF S% <> O% THEN
          O% = S%
          VDU 24,0;0;@vdu%!208*2-2;@vdu%!212*2-2;
          IF S% >= 0 THEN
            PROCdrawstatusbar(m%(S%) AND &FFF, FALSE, FALSE)
          ELSE
            PROCdrawstatusbar(D% - IDMENU1 + 1, FALSE, FALSE)
          ENDIF
        ENDIF
        
      UNTIL FALSE
      
      *REFRESH ON
      VDU 24,0;0;@vdu%!208*2-2;@vdu%!212*2-2;
      IF S% >= -1 PROCdrawstatusbar(0, FALSE, FALSE)
      OSCLI "FONT " + EditFont$
      OSCLI "DISPLAY """ + @tmp$ + "bbc" + Session$ + ".tmp.bmp" + """ " + STR$X% + "," + STR$(Y%-H%)
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0;5 : REM Set cursor width
      IF D% = IDPOPUP PROCcursor(1)
      Refresh% = TRUE : REM To reset caret
      = S%
      
      DEF FNcombo(m$(), N%, X%, Y%, W%)
      LOCAL A%, B%, C%, D%, H%, I%, K%, L%, M%, P%, Q%, R%, S%, T%, U%, click%
      LOCAL sb{} : DIM sb{} = ScrlBarV{}
      ON TIME LOCAL OFF
      ON MOUSE LOCAL click% = TRUE : RETURN
      
      OSCLI "FONT " + GUIFont$
      C% = @vdu%!220 * 2
      H% = N% * C% + 8
      IF (Y% - H%) < C% H% = Y% - C%
      W% = (W% + 1) AND -2 : REM must be even
      
      sb.l% = X% + W% - SCROLLBARSIZE
      sb.t% = Y% - SCROLLBARSIZE + 2
      sb.r% = X% + W% - 4
      sb.b% = Y% - H% + SCROLLBARSIZE
      
      OSCLI "GSAVE """ + @tmp$ + "bbc" + Session$ + ".tmp.bmp" + """ " + STR$X% + "," + STR$(Y%-H%) + \
      \     "," + STR$(W%+2) + "," + STR$(H%+2)
      
      VDU 24,X%;Y%-H%+2;X%+W%-2;Y%-2;5
      
      M% = H% DIV C%
      S% = 0
      L% = 0
      MOUSE P%, Q%, B%
      REPEAT
        *REFRESH OFF
        PROCcursor(0)
        GCOL COL_GUITEXT
        GCOL 128 + COL_EDITPANE
        VDU 16,30,23,16,64|
        FOR I% = L% + 1 TO L% + M%
          IF I% > DIM(m$(),1) EXIT FOR
          GCOL COL_GUITEXT
          PRINT "  " m$(I%)
          IF I% = S% THEN
            GCOL 2,128 + COL_HILITEAND
            PLOT 99,W%,C%
            GCOL 1,128 + COL_HILITEOR
            PLOT 99,-W%,-C%
            GCOL 0,128 + COL_SELECT
            PLOT 3,0,C% : PLOT 3,W%,0
            PLOT 3,0,-C% : PLOT 3,-W%,0
          ENDIF
        NEXT
        
        sb.max% = N% * C%
        sb.pos% = L% * C%
        sb.page% = M% * C%
        PROC_drawscrollbar(0, sb{})
        RECTANGLE X%, Y% - 2, W% - 2, -H% + 6
        LINE sb.l%-2, Y%, sb.l%-2, Y%-H%
        
        MOUSE I%, T%, B%
        IF B% = 0 D% = 0 : A% = 0
        IF I%<>P% OR T%<>Q% THEN
          IF D% = 2 THEN
            A% += (T% - Q%) * sb.scale
          ELSE
            A% = 0
          ENDIF
          P% = I% : Q% = T%
          IF D% = 0 THEN
            P% = I% : Q% = T%
            IF P% > X% IF P% < X%+W%-SCROLLBARSIZE THEN
              T% = Y%
              FOR I% = L% TO L% + M%
                IF Q% > T% IF Q% < T% + C% THEN
                  S% = I%
                  IF S% < 1 S% = 1
                  IF S% > N% S% = N%
                  WHILE S% <= L%       L% -= 1 : ENDWHILE
                  WHILE S% > (L% + M%) L% += 1 : ENDWHILE
                ENDIF
                T% -= C%
              NEXT
            ENDIF
          ENDIF
          IF P% < X% OR P% > X%+W% OR Q% > Y% OR Q% < Y%-H% S% = 0
        ENDIF
        WHILE A% > C% L% -= 1 : A% -= C% : ENDWHILE
        WHILE A% < 0  L% += 1 : A% += C% : ENDWHILE
        
        IF L% > N% - M% L% = N% - M%
        IF L% < 0 L% = 0
        
        I% = P% : T% = Q%
        IF D% = 2 I% = (sb.l% + sb.r%) DIV 2 : T% = (sb.thumb.t% + sb.thumb.b%) DIV 2
        B% = FN_sbhotspot(0, sb{}, I%, T%)
        IF B% >= 0 THEN
          S% = 0
          PROC_sbhotspot(B%, sb{}, I%, T%, R%, U%)
          IF R% IF U% THEN
            GCOL 2, COL_HILITEAND
            RECTANGLE FILL I%, T%, R%, U%
            GCOL 1, COL_HILITEOR
            RECTANGLE FILL I%, T%, R%, U%
          ENDIF
        ENDIF
        *REFRESH
        
        IF click% THEN
          click% = FALSE
          CASE B% OF
            WHEN 0,1,3,4:
              D% = 1
              RepTimer% = 0
            WHEN 2:
              D% = 2
              RepTimer% = 0
            OTHERWISE:
              EXIT REPEAT
          ENDCASE
        ENDIF
        
        IF D% IF RepTimer% = 0 OR RepTimer% > 8 THEN
          CASE B% OF
            WHEN 0: L% -= 1  : IF L% < 0 L% = 0
            WHEN 1: L% -= M% : IF L% < 0 L% = 0
            WHEN 3: L% += M% : IF L% > N% - M% L% = N% - M%
            WHEN 4: L% += 1  : IF L% > N% - M% L% = N% - M%
          ENDCASE
        ENDIF
        RepTimer% += 1
        
        K% = INKEY(4)
        CASE K% OF
          WHEN 13: EXIT REPEAT
          WHEN 27: S% = 0 : EXIT REPEAT
          WHEN 138: S% = (S% + N%) MOD N% + 1
          WHEN 139: S% = (S% + N% - 2) MOD N% + 1
          WHEN 140: L% += 1 : IF L% > N% - M% L% = N% - M%
          WHEN 141: L% -= 1 : IF L% < 0 L% = 0
          WHEN 132: L% -= M% : IF L% < 0 L% = 0
          WHEN 133: L% += M% : IF L% > N% - M% L% = N% - M%
        ENDCASE
        IF K% <> -1 IF K% < 140 IF K% > 133 THEN
          WHILE S% <= L%       L% -= 1 : ENDWHILE
          WHILE S% > (L% + M%) L% += 1 : ENDWHILE
        ENDIF
        
      UNTIL FALSE
      
      OSCLI "FONT " + EditFont$
      OSCLI "DISPLAY """ + @tmp$ + "bbc" + Session$ + ".tmp.bmp" + """ " + STR$X% + "," + STR$(Y%-H%)
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      VDU 24,0;0;@vdu%!208*2-2;@vdu%!212*2-2;4
      Refresh% = TRUE : REM To reset caret
      
      = S%
      
      DEF FNfileselector(t$)
      LOCAL C%, H%, W%, X%, Y%, a$, d$
      
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      
      OSCLI "FONT " + GUIFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      OFF
      
      IF INSTR(t$,"Save") THEN
        PROC_setdialogtitle(FileDlg%, t$)
        PROC_setdlgitemtext(FileDlg%, 1, "Save")
        PROC_showdlgitem(FileDlg%, 106, 1)
        PROC_showdlgitem(FileDlg%, 107, 1)
        PROC_showdlgitem(FileDlg%, 108, 0)
        PROC_showdlgitem(FileDlg%, 109, 0)
        IF FN_lower(RIGHT$(CurrentFile$, 4)) = ".bbc" OR CurrentFile$ = "" THEN
          PROC_checkdlgitem(FileDlg%, 106, 1)
          PROC_checkdlgitem(FileDlg%, 107, 0)
        ELSE
          PROC_checkdlgitem(FileDlg%, 106, 0)
          PROC_checkdlgitem(FileDlg%, 107, 1)
        ENDIF
      ELSE
        PROC_setdialogtitle(FileDlg%, t$)
        PROC_setdlgitemtext(FileDlg%, 1, "Open")
        PROC_showdlgitem(FileDlg%, 106, 0)
        PROC_showdlgitem(FileDlg%, 107, 0)
        PROC_showdlgitem(FileDlg%, 108, 1)
        PROC_showdlgitem(FileDlg%, 109, 1)
        PROC_checkdlgitem(FileDlg%, 106, 0)
        PROC_checkdlgitem(FileDlg%, 107, 0)
        PROC_checkdlgitem(FileDlg%, 108, 1)
        PROC_checkdlgitem(FileDlg%, 109, 0)
      ENDIF
      
      a$ = FNgetcwd + RIGHT$(@lib$)
      PROC_setdlgitemtext(FileDlg%, 102, a$)
      PROC_registerdlgcallback(FileDlg%, FNfscb())
      
      X% = &80000000 : Y% = &80000000
      REPEAT
        C% = FN_showdialogex(FileDlg%, X%, Y%, Darkmode%)
        PROC_getdlgrect(FileDlg%, X%, Y%, W%, H%)
        a$ = FN_getdlgitemtext(FileDlg%, 104)
        d$ = FN_getdlgitemtext(FileDlg%, 102)
      UNTIL C% = 1 OR C% = 2
      PROC_closedialog(FileDlg%)
      
      IF FN_isdlgitemchecked(FileDlg%, 106) IF FN_lower(RIGHT$(a$,4)) <> ".bbc" a$ += ".bbc"
      IF FN_isdlgitemchecked(FileDlg%, 107) IF FN_lower(RIGHT$(a$,4)) <> ".bas" a$ += ".bas"
      IF INSTR(a$,".") = 0 a$ += "."
      
      PROC_closedialog(FileDlg%)
      
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      Refresh% = TRUE : REM To reset caret
      
      IF C% = 2 THEN = ""
      IF ASCa$ = &2F OR ASCa$ = &5C THEN = a$
      = d$ + a$
      
      DEF FNfscb(D%,K%)
      LOCAL N%, R%, a$, t$
      PRIVATE B%, E%, F%, T%, d$, f$, s$, n$()
      DIM n$(10000)
      IF F% <> FN_isdlgitemchecked(D%,109) THEN
        F% = NOT F%
        d$ = ""
      ENDIF
      a$ = FN_getdlgitemtext(D%,102)
      IF a$ <> d$ IF RIGHT$(a$) = "/" OR RIGHT$(a$) = "\" THEN
        d$ = a$
        ON ERROR LOCAL IF FALSE THEN
          OSCLI "cd """ + a$ + """"
          IF FN_isdlgitemchecked(D%,109) THEN
            N% = FNdirscan(n$(), "dir *.*", "", Folder$, BBfile$)
          ELSE
            N% = FNdirscan(n$(), "dir *.*", ".bas;.bbc", Folder$, BBfile$)
          ENDIF
          PROC_setdlgitemtext(D%, 102, n$(0))
        ELSE
          N% = 3
        ENDIF : RESTORE ERROR
        PROC_setlistboxarray(D%, IDlistbox%, n$(), N%)
        IF FN_getdlgitemtext(D%, 1) = "Open" THEN
          PROC_setdlgitemtext(D%, 104, "")
        ENDIF
        PROC_setlistboxselect(D%, IDlistbox%, -1)
        PROC_refreshdialog(D%)
      ENDIF
      a$ = FN_getdlgitemtext(D%,IDlistbox%)
      IF a$ <> s$ THEN
        s$ = a$
        IF LEFT$(a$, LEN(BBfile$)) = BBfile$ THEN
          PROC_setdlgitemtext(D%, 104, FN_trim(MID$(a$, LEN(BBfile$) + 1)))
          PROC_refreshdialog(D%)
        ENDIF
      ENDIF
      a$ = FN_getdlgitemtext(D%,104)
      IF a$ <> f$ IF a$ <> "" THEN
        f$ = a$
        IF BBfile$ + a$ <> FN_getdlgitemtext(D%, IDlistbox%) THEN
          N% = FNchops(n$(), BBfile$ + a$) + 1
          PROC_setlistboxselect(D%, IDlistbox%, N%)
          PROC_refreshdialog(D%)
          s$ = n$(N%)
        ENDIF
      ENDIF
      IF E% <> (a$ = "") THEN
        E% = (a$ = "")
        PROC_enabledlgitem(D%,1,NOT E%)
        PROC_refreshdialog(D%)
      ENDIF
      t$ = a$
      N% = FNinstrr(t$, ".", 0)
      IF N% = 0 B% = 0 : T% = 0
      IF B% <> FN_isdlgitemchecked(D%,106) THEN
        B% = NOT B%
        IF B% t$ = LEFT$(t$, N%-1) + ".bbc" : f$ = t$
      ENDIF
      IF T% <> FN_isdlgitemchecked(D%,107) THEN
        T% = NOT T%
        IF T% t$ = LEFT$(t$, N%-1) + ".bas" : f$ = t$
      ENDIF
      IF a$ <> t$ IF a$ <> "" THEN
        PROC_setdlgitemtext(D%, 104, t$)
        PROC_refreshdialog(D%)
      ENDIF
      R% = FN_getdlgfocus(D%) : IF R% > 9 R% = 1
      IF K% = 27 THEN = 2
      IF NOT E% IF K% = 13 THEN = R%
      = 0
      
      DEF PROClistclick(D%, I%)
      LOCAL a$, d$, t$
      t$ = FN_getdlgitemtext(D%, I%)
      a$ = FN_trim(MID$(t$, LEN(BBfile$) + 1))
      d$ = FN_getdlgitemtext(D%, 102)
      IF a$ = "" ENDPROC
      IF LEFT$(t$, LEN(BBfile$)) = BBfile$ THEN
        PROC_setdlgitemtext(D%, 104, a$)
      ELSE
        IF ASC(a$) = &40 a$ = EVAL(a$) ELSE a$ = d$ + a$ + RIGHT$(@lib$)
        PROC_setdlgitemtext(D%, 102, a$)
        PROC_setlistboxselect(D%, I%, 0)
      ENDIF
      PROC_refreshdialog(D%)
      ENDPROC
      
      REM Scan a directory and return list of directory and file names
      REM icon1$ is a directory prefix, icon2$ is a file prefix
      DEF FNdirscan(name$(), dircmd$, filter$, icon1$, icon2$)
      LOCAL C%, F%, I%, N%, a$, d$, type&()
      DIM type&(DIM(name$(),1))
      
      REM Spool *DIR output to a temporary file:
      WIDTH 20
      VDU 21
      ON ERROR LOCAL IF FALSE THEN
        OSCLI "spool """ + @tmp$ + "dir.tmp.txt"""
        OSCLI dircmd$
      ENDIF : RESTORE ERROR
      *spool
      VDU 6
      WIDTH 0
      
      REM Parse the file to extract directory names and filenames.
      REM Cope with long filenames if they have split between lines
      N% = 0
      type&() = 0
      name$() = ""
      F% = OPENIN(@tmp$ + "dir.tmp.txt")
      REPEAT
        INPUT #F%,a$
        IF ASCa$ = &A a$ = MID$(a$,2)
        IF LEFT$(a$,2)="  " OR LEFT$(a$,2)="* " OR EOF#F% IF a$<>STRING$(20," ") THEN
          IF N% = 0 THEN
            d$ = name$(0)
            C% = FN_instrr(d$, "/", 0) : IF C% IF MID$(d$, C% - 1, 1) = "/" C% -= 1
            IF C% = 0 C% = FN_instrr(d$, "\", 0) : IF MID$(d$, C% - 1, 1) = "\" C% -= 1
            name$(0) = MID$(d$, 14, C% - 13)
            N% += 1 : REM Zeroth index holds directory name
          ELSE
            name$(N%) = FN_trim(name$(N%))
            d$ = FN_lower(name$(N%))
            ON ERROR LOCAL IF FALSE THEN
              OSCLI "cd """ + name$(0) + name$(N%) + """"
              OSCLI "cd """ + name$(0) + """"
              IF d$<>"." IF d$<>".." IF filter$="" OR ASCd$<>&2E type&(N%) = 1 : N% += 1
            ELSE
              IF filter$="" OR INSTR(filter$,RIGHT$(d$,4)) type&(N%) = 2 : N% += 1
            ENDIF : RESTORE ERROR
          ENDIF
          name$(N%) = MID$(a$,3)
        ELSE
          name$(N%) += a$
        ENDIF
      UNTIL EOF#F% OR N% >= DIM(name$(),1)
      CLOSE #F%
      
      IF icon1$ <> "" THEN
        IF N% < DIM(name$(),1) name$(N%) = "@lib$" : type&(N%) = 0 : N% += 1
        IF N% < DIM(name$(),1) name$(N%) = "@usr$" : type&(N%) = 0 : N% += 1
        name$(N%) = ".." : type&(N%) = 0 : N% += 1
      ENDIF
      N% -= 1
      
      REM Sort the array so directories are listed before programs:
      C% = N%
      CALL Sort%%, type&(1), name$(1)
      
      REM Add icons:
      FOR I% = 1 TO N%
        IF type&(I%) = 2 name$(I%) = icon2$ + name$(I%) ELSE name$(I%) = icon1$ + name$(I%)
      NEXT
      
      = N%
      
      REM!Eject --------------------------------------------------------------------------
      DEF __Helper_Routines__
      
      DEF PROCinsert(f$(), i%(), RETURN cx%, cy%, k$)
      LOCAL a$, l$, r$, I%
      I% = i%(cy%)
      a$ = FNformat(f$(cy%), I%)
      PROCsplitx(a$, cx%, l$, r$)
      cx% += FNlen(k$)
      PROCreformat(l$ + k$ + r$, cx%, cy%, f$(), i%(), FALSE)
      ENDPROC
      
      DEF PROCovertype(f$(), i%(), RETURN cx%, cy%, k$)
      LOCAL a$, l$, r$, I%
      I% = i%(cy%)
      a$ = FNformat(f$(cy%), I%)
      PROCsplitx(a$, cx%, l$, r$)
      PROCsplitx(a$, cx% + LENk$, a$, r$)
      cx% += FNlen(k$)
      PROCreformat(l$ + k$ + r$, cx%, cy%, f$(), i%(), FALSE)
      ENDPROC
      
      DEF PROCundosave(f$(), b&(), nl%, RETURN ul%, RETURN rl%, cx%, cy%)
      LOCAL F%
      PROCredoclear(ul%, rl%)
      F% = OPENOUT(@tmp$ + "undo" + Session$ + STR$ul% + ".tmp.bbc")
      BPUT#F%, SUM(f$());
      b&(DIM(b&(),1)) = &D
      BPUT#F%,0 : PRINT #F%, cx%, cy%, LEFT$($^b&(0), nl%)
      CLOSE #F%
      ul% += 1
      ENDPROC
      
      DEF PROCundoclear(RETURN ul%, RETURN rl%)
      PROCredoclear(ul%, rl%)
      WHILE ul%
        ul% -= 1
        OSCLI "DEL """ + @tmp$ + "undo" + Session$ + STR$ul% + ".tmp.bbc"""
      ENDWHILE
      ENDPROC
      
      DEF PROCredoclear(ul%, RETURN rl%)
      IF rl% THEN
        WHILE rl% >= ul%
          OSCLI "DEL """ + @tmp$ + "undo" + Session$ + STR$rl% + ".tmp.bbc"""
          rl% -= 1
        ENDWHILE
        rl% = 0
      ENDIF
      ENDPROC
      
      DEF PROCsetpalette
      LOCAL C%, I%, key$
      
      IF Darkmode% THEN
        key$ = "dark"
        Colours%() = &FFC000, &FF80FF, &FF0000, &80C000, &0080FF, &FFFFFF
        COLOR COL_GUITEXT,   &FF, &FF, &FF : REM GUI text colour (white)
        COLOR COL_GUIBKGD,   &40, &40, &40 : REM Primary GUI background colour
        COLOR COL_BORDERS,   &80, &80, &80 : REM Primary GUI foreground colour
        COLOR COL_DISABLED,  &7F, &7F, &7F : REM Disabled menus/buttons (ANDed)
        COLOR COL_PRESSED,   &60, &60, &60 : REM Pressed buttons (ORed)
        COLOR COL_HILITEAND, &FF, &FF, &FF : REM Hotspot highlight AND (first)
        COLOR COL_HILITEOR,  &00, &7F, &7F : REM Hotspot highlight OR (second)
        COLOR COL_SELECT,    &00, &7F, &FF : REM Selected text background
        COLOR COL_ICONS,     &C0, &C0, &00 : REM Folder and BBfile icon yellow
        COLOR COL_EDITPANE,  &10, &10, &10 : REM Edit background & scrollbars
      ELSE
        key$ = "colour"
        Colours%() = &FF8000, &FF00FF, &FF0000, &008000, &0000FF, &000000
        COLOR COL_GUITEXT,   &00, &00, &00 : REM GUI text colour (black)
        COLOR COL_GUIBKGD,   &F0, &F0, &F0 : REM Primary GUI background colour
        COLOR COL_BORDERS,   &80, &80, &80 : REM Primary GUI foreground colour
        COLOR COL_DISABLED,  &B0, &B0, &B0 : REM Disabled menus/buttons (ORed)
        COLOR COL_PRESSED,   &D0, &D0, &D0 : REM Pressed buttons (ANDed)
        COLOR COL_HILITEAND, &80, &E0, &FF : REM Hotspot highlight AND (first)
        COLOR COL_HILITEOR,  &00, &1F, &3F : REM Hotspot highlight OR (second)
        COLOR COL_SELECT,    &00, &80, &FF : REM Selected text background
        COLOR COL_ICONS,     &C0, &C0, &00 : REM Folder and BBfile icon yellow
        COLOR COL_EDITPANE,  &FF, &FF, &FF : REM Edit background & scrollbars
      ENDIF
      
      FOR I% = 1 TO 6
        C% = VALFNgetINIstring(IniFile$, key$ + STR$(I%), STR$(Colours%(I%-1)))
        Colours%(I%-1) = C%
        IF Colouring% THEN
          COLOR I%, (C% AND &FF0000) >> 16, (C% AND &FF00) >> 8, C% AND &FF
        ELSE
          IF Darkmode% COLOR I%, &FF, &FF, &FF ELSE COLOR I%, 0, 0, 0
        ENDIF
      NEXT
      ENDPROC
      
      REM Search program for a given string:
      DEF FNsearch(s$, f$(), i%(), nl%, fl%, RETURN ax%, RETURN ay%, RETURN cx%, RETURN cy%)
      LOCAL a$, C%, I%, M%, W%, Y%
      W% = (fl% AND &10000) <> 0
      C% = (fl% AND &20000) <> 0
      IF NOT C% s$ = FN_lower(s$)
      Y% = cy%
      I% = i%(Y%)
      REPEAT
        a$ = FNstrip(FNformat(f$(Y%), I%))
        IF NOT C% a$ = FN_lower(a$)
        IF Y% = cy% M% = cx% ELSE M% = 0
        REPEAT
          IF Unicode% M% = FN_upos(a$, M%)
          M% = INSTR(a$, s$, M%+1)
          IF M% THEN
            IF W% IF INSTR(Valid$,(MID$(a$,M%-1,1))) OR INSTR(Valid$,MID$(a$,M%+LENs$,1)) THEN
            ELSE
              a$ = LEFT$(a$, M%-1)
              M% += FNlen(a$) - LEN(a$) : REM UTF-8 adjustment
              ax% = M%-1 : ay% = Y%
              cx% = M%+FNlen(s$)-1 : cy% = Y%
              = TRUE
            ENDIF
          ENDIF
        UNTIL M%=0
        Y% += 1
      UNTIL Y% >= nl%
      = FALSE
      
      REM Return selected text:
      DEF FNseltext(f$(), i%(), x1%, y1%, x2%, y2%)
      LOCAL I%, Y%, a$, b$
      IF x1% > x2% SWAP x1%,x2%
      IF y1% > y2% SWAP y1%,y2%
      CASE TRUE OF
        WHEN y1% <> y2%:
          FOR Y% = y1% TO y2%-1
            I% = i%(Y%)
            a$ += FNstrip(FNformat(f$(Y%), I%)) + CHR$&D + CHR$&A
          NEXT
        WHEN x1% <> x2%:
          I% = i%(y1%)
          a$ = FNformat(f$(y1%), I%)
          PROCsplitx(a$, x1%, b$, a$)
          PROCsplitx(a$, x2%-x1%, a$, b$)
          a$ = FNstrip(a$)
      ENDCASE
      = a$
      
      REM Test if clipboard text is available:
      DEF FNhascliptext
      LOCAL F%
      IF BB4W% THEN
        SYS "IsClipboardFormatAvailable", 1 TO F%
      ELSE IF (@platform% AND &F) <> 5 THEN;
        SYS "SDL_HasClipboardText" TO F%
      ENDIF
      = F% <> 0
      
      REM Test if all selected lines begin with REM
      DEF FNisallrems(f$(), cy%, ay%)
      LOCAL F%,I%
      IF ay% = cy% THEN = FALSE
      IF ay% < cy% SWAP ay%,cy%
      F% = TRUE
      FOR I% = cy% TO ay%-1
        IF ASCMID$(f$(I%), 4) <> &F4 F% = FALSE
      NEXT
      = F%
      
      DEF FNisfnproc(f$(), i%(), X%, Y%, N%, RETURN I%)
      LOCAL A%, a$, f$
      PROCpointtochar(X%, Y%)
      I% = i%(Y%)
      f$ = FNstrip(FNformat(f$(Y%), I%))
      FOR I% = 0 TO N%-1
        IF ASCMID$(f$(I%),4)=&DD THEN
          A% = 0
          a$ = MID$(FNstrip(FNformat(f$(I%),A%)),7)
          a$ = MID$(a$,4)
          A% = INSTR(a$,"(") : IF A% a$ = LEFT$(a$,A%)
          A% = INSTR(a$,":") : IF A% a$ = LEFT$(a$,A%-1)
          a$ = FN_trim(a$)
          A% = INSTR(f$, a$)
          IF RIGHT$(a$) <> "(" IF MID$(f$, A%+LENa$, 1) = "(" A% = 0
          IF RIGHT$(a$) = "(" a$ += ")" ELSE IF INSTR(Valid$ + "@_`", MID$(f$, A% + LENa$, 1)) A% = 0
          IF A% IF X% >= A% IF X% < (A% + LENa$) THEN = a$
        ENDIF
      NEXT
      I% = -1
      = ""
      
      DEF PROCsavejump(goback%(), scrolly%, RETURN glevel%)
      LOCAL I%
      goback%(glevel%) = scrolly%
      IF glevel% < DIM(goback%(),1) THEN
        glevel% += 1
      ELSE
        FOR I% = 0 TO glevel%-1
          goback%(I%) = goback%(I%+1)
        NEXT
      ENDIF
      ENDPROC
      
      DEF PROCexecute(bbcfile$, flag$)
      ON ERROR LOCAL IF FALSE THEN
        IF BB4W% THEN
          OSCLI "RUN """ + @lib$ + "..\bbcwrun6.exe"" """ + bbcfile$ + """ " + flag$ + ";"
        ELSE
          CASE @platform% AND &F OF
            WHEN 0:
              SYS "WinExec", """" + @lib$ + "..\bbcsdl"" """ + bbcfile$ + """ " + flag$, 1
            OTHERWISE:
              OSCLI "RUN """ + @lib$ + "../bbcsdl"" """ + bbcfile$ + """ " + flag$ + ";"
          ENDCASE
        ENDIF
      ENDIF : RESTORE ERROR
      ENDPROC
      
      DEF PROCopenurl(url$)
      IF BB4W% THEN
        SYS "ShellExecute", @hwnd%, "open", url$, 0, 0, 1
      ELSE
        CASE @platform% AND &F OF
          WHEN 0:
            SYS "WinExec", "cmd /cstart " + url$ + "&", 0
          WHEN 1:
            SYS "system", "xdg-open " + url$ + "&"
          WHEN 2:
            SYS "system", "open " + url$ + "&"
          WHEN 5:
            SYS "emscripten_run_script_string", "window.open(""" + url$ + """, ""_blank"")", @memhdc%
        ENDCASE
      ENDIF
      ENDPROC
      
      DEF PROCtitle(name$)
      name$ += " - " + Title$
      IF BB4W% THEN
        SYS "SetWindowText", @hwnd%, name$
      ELSE
        SYS "SDL_SetWindowTitle", @hwnd%, name$, @memhdc%
      ENDIF
      ENDPROC
      
      DEF PROCload(file$, RETURN nl%, RETURN ml%, in%)
      LOCAL B%, F%, H%, I%, L%, N%, T%, a$
      
      F% = FN_instrr(file$, ".", 0)
      B% = FN_instrr(file$, "/", 0) : IF B% = 0 B% = FN_instrr(file$, "\", 0)
      IF F% <= B% file$ += ".bbc"
      
      F% = OPENIN(file$)
      IF F% = 0 THEN
        PROCmessagebox("SDLIDE", "Couldn't open file '" + file$ + "'", 0)
        ENDPROC
      ENDIF
      
      ON TIME LOCAL OFF : REM Prevent mouse cursor change
      
      IF in% THEN
        LOCAL t$()
        DIM t$(nl% - CaretY%)
        FOR I% = 0 TO nl% - CaretY%
          SWAP t$(I%), Buffer$(CaretY% + I%)
        NEXT
        I% = CaretY%
        N% = Indent%(I%)
      ELSE
        ml% = 0
        Buffer$() = ""
        Indent%() = 0
      ENDIF
      
      PROCcursor(2)
      T% = SGN(FNvalidbbc(F%) - FNvalidacorn(F%))
      IF T% = TRUE B% = BGET#F%
      
      WHILE NOT EOF#F%
        CASE T% OF
          WHEN +1:
            B% = BGET#F% : IF B% = 0 Buffer$(I%) = "" : EXIT WHILE
            Buffer$(I%) = CHR$B% + GET$#F% BY (B%-1)
            
          WHEN -1:
            H% = BGET#F% : IF H% = &FF Buffer$(I%) = "" : EXIT WHILE
            L% = BGET#F% : B% = BGET#F% : a$ = GET$#F% BY (B%-3)
            WHILE ASCa$=&20 a$ = MID$(a$,2) : B% -= 1 : ENDWHILE
            IF FNinstrq(a$, CHR$&7F, 1) OR FNinstrq(a$, CHR$&CC, 1) a$ = FNacorntoken1(a$)
            IF FNinstrq(a$, CHR$&C6, 1) OR FNinstrq(a$, CHR$&C8, 1) a$ = FNacorntoken2(a$, B%)
            IF FNinstrq(a$, "BY", 1) a$ = FNacorntoken3(a$)
            Buffer$(I%) = CHR$B% + CHR$L% + CHR$H% + a$
            
          OTHERWISE:
            a$ = GET$#F%
            IF a$="" IF PTR#F%>1 THEN PTR#F%=PTR#F%-2 : IF BGET#F%<>BGET#F% a$ = GET$#F%
            REPEAT H% = INSTR(a$,CHR$9) : IF H% MID$(a$,H%,1) = " "
            UNTIL H% = 0
            IF a$<>"" IF ASCa$<&20 PROCmessagebox("SDLIDE", "Invalid file format", 0) : EXIT WHILE
            IF EOF#F% IF a$ = "" Buffer$(I%) = "" : EXIT WHILE
            Buffer$(I%) = FNtokenise(a$)
        ENDCASE
        Indent%(I%) = N%
        PROCindent(Buffer$(I%), N%, ml%)
        I% += 1
      ENDWHILE
      CLOSE #F%
      
      IF in% THEN
        FOR B% = 0 TO nl% - CaretY%
          Buffer$(I%) = t$(B%)
          Indent%(I%) = N%
          PROCindent(Buffer$(I%), N%, ml%)
          I% += 1
        NEXT
        PROCcursor(0)
      ENDIF
      nl% = I%
      WHILE I% <= DIM(Indent%(),1)
        Indent%(I%) = N%
        I% += 1
      ENDWHILE
      IF in% ENDPROC
      
      F% = 0
      FOR I% = 0 TO nl% - 1
        F% OR= FNansi_or_utf8(Buffer$(I%))
      NEXT
      IF Unicode% THEN
        IF F% = 1 IF FNmessagebox("SDLIDE", "Switching to ANSI", 1) = 1 Unicode% = FALSE
      ELSE
        IF F% = 2 IF FNmessagebox("SDLIDE", "Switching to Unicode", 1) = 1 Unicode% = TRUE
      ENDIF
      
      F% = FNinstrr(file$, "/", 0)
      IF F% = 0 F% = FNinstrr(file$, "\", 0)
      IF F% = 0 THEN
        file$ = FNgetcwd + RIGHT$(@lib$) + file$
      ELSE
        OSCLI "cd """ + LEFT$(file$, F%-1) + """"
      ENDIF
      CurrentFile$ = file$
      PROCtitle(CurrentFile$)
      PROCupdaterecent(CurrentFile$)
      IF T% = TRUE CurrentFile$ = "" : REM Disable 'Save' if Acorn format
      PROCundoclear(UndoLevel%, RedoLevel%)
      PROCcursor(0)
      ENDPROC
      
      DEF FNsave(file$)
      LOCAL F%, I%, N%
      
      F% = OPENOUT(file$)
      IF F% = 0 THEN
        PROCmessagebox("SDLIDE", "Couldn't create file '" + file$ + "'", 0)
        = FALSE
      ENDIF
      
      IF FN_lower(RIGHT$(file$,4)) = ".bbc" THEN
        BPUT#F%, SUM(Buffer$());
        BPUT#F%, 0
        BPUT#F%, &FF
        BPUT#F%, &FF
      ELSE
        I% = Indent%(0)
        FOR N% = 0 TO nLines% - 1
          PRINT #F%, FNstrip(FNformat(Buffer$(N%), I%))
          BPUT #F%, 10
        NEXT
      ENDIF
      CLOSE #F%
      
      = TRUE
      
      DEF FNgetcwd
      LOCAL F%, a$, f$
      f$ = @tmp$ + "cwd.tmp.txt"
      VDU 21
      OSCLI "spool """ + f$ + """"
      ON ERROR LOCAL IF FALSE THEN
        *cd
      ENDIF : RESTORE ERROR
      *spool
      VDU 6
      F% = OPENIN(f$)
      a$ = FNstrip(GET$#F%)
      CLOSE #F%
      = a$
      
      DEF FNnopath(f$)
      LOCAL N%
      N% = FNinstrr(f$, "/", 0)
      IF N%=0 N% = FNinstrr(f$, "\", 0)
      IF N% f$ = MID$(f$, N%+1)
      = f$
      
      DEF FNpath(f$)
      LOCAL N%
      N% = FNinstrr(f$, "/", 0)
      IF N%=0 N% = FNinstrr(f$, "\", 0)
      = LEFT$(f$, N%)
      
      DEF FNnoext(f$)
      LOCAL N%
      N% = FNinstrr(f$, ".", 0)
      = LEFT$(f$, N%-1)
      
      DEF FNvalidbbc(F%)
      LOCAL L%, P%
      REPEAT
        L% = BGET#F%
        IF L%=0 THEN PTR#F% = 0 : = P%
        P% += L%
        PTR#F% = P% - 1
      UNTIL BGET#F%<>&D OR EOF#F%
      PTR#F% = 0
      = FALSE
      
      DEF FNvalidacorn(F%)
      LOCAL L%, P% : L% = 1
      WHILE BGET#F%=&D AND L%<>0 AND NOT EOF#F%
        IF BGET#F%=&FF THEN PTR#F% = 0 : = P%
        L% = BGET#F% : L% = BGET#F%
        P% += L%
        PTR#F% = P%
      ENDWHILE
      PTR#F% = 0
      = FALSE
      
      DEF FNacorntoken1(a$)
      LOCAL I%
      REPEAT I% = FNinstrq(a$, CHR$&CC, I% + 1) : IF I% MID$(a$, I%, 1) = CHR$&8B : REM multiline ELSE
      UNTIL I% = 0
      REPEAT I% = FNinstrq(a$, CHR$&7F, I% + 1) : IF I% MID$(a$, I%, 1) = CHR$&CC : REM OTHERWISE
      UNTIL I% = 0
      = a$
      
      DEF FNacorntoken2(a$, RETURN B%)
      LOCAL I%, T%
      REPEAT I% = FNinstrq(a$, CHR$&C6 + CHR$&8E, I% + 1)
        IF I% a$ = LEFT$(a$, I%) + MID$(a$, I% + 2) : B% -= 1 : REM SUM
      UNTIL I% = 0
      REPEAT I% = FNinstrq(a$, CHR$&C8, I% + 1)
        IF I% THEN
          T% = ASCMID$(a$, I% + 1, 1) - &8E
          IF T% >= 0 IF T% <= 15 THEN
            a$ = LEFT$(a$, I% - 1) + CHR$Acorn&(T%) + MID$(a$, I% + 2) : B% -= 1
          ENDIF
        ENDIF
      UNTIL I% = 0
      = a$
      
      DEF FNacorntoken3(a$)
      LOCAL I%, J%
      REPEAT I% = FNinstrq(a$, "BY", I% + 1)
        IF I% THEN
          J% = I% : REPEAT J% -= 1 UNTIL MID$(a$, J%, 1) <> " "
          IF INSTR(CHR$&DF + CHR$&03 + CHR$&EC + CHR$&F0, MID$(a$, J%, 1)) THEN
            a$ = LEFT$(a$, I% - 1) + CHR$(&0F) + " " + MID$(a$, I% + 2) : REM BY
          ENDIF
        ENDIF
      UNTIL I% = 0
      =a$
      
      DEF PROCdebugcmd(W%, L%)
      LOCAL F%
      REPEAT
        F% = OPENOUT(@tmp$ + "sdldebug.cmd")
        IF F% = 0 WAIT RND(3)
      UNTIL F%
      BPUT#F%,W% : BPUT#F%,W% >> 8 : BPUT#F%,W% >> 16 : BPUT#F%,W% >> 24
      BPUT#F%,L% : BPUT#F%,L% >> 8 : BPUT#F%,L% >> 16 : BPUT#F%,L% >> 24
      CLOSE #F%
      ENDPROC
      
      DEF PROChilite(N%)
      LOCAL H%, I%, W%, X%, Y%
      PROChotspot(N%, X%, Y%, W%, H%)
      IF POS REM SDL thread sync.
      LOCAL @vdu%!64, @vdu.l.x%, @vdu.l.y%, @vdu.p.x%, @vdu.p.y%
      *REFRESH OFF
      IF Darkmode% THEN
        OSCLI "DISPLAY """+@dir$+"SDLIDEdark"" 0," + STR$INT(2*@vdu%!212 - BMPHEIGHT) + \
        \                                      "," + STR$INT(BMPWIDTH) + "," + STR$INT(BMPHEIGHT)
      ELSE
        OSCLI "DISPLAY """+@dir$+"SDLIDE"" 0," + STR$INT(2*@vdu%!212 - BMPHEIGHT) + \
        \                                  "," + STR$INT(BMPWIDTH) + "," + STR$INT(BMPHEIGHT)
      ENDIF
      GCOL COL_EDITPANE
      RECTANGLE FILL ComboBox.l%, ComboBox.b%, ComboBox.r%-ComboBox.l%, ComboBox.t%-ComboBox.b%
      GCOL COL_BORDERS
      RECTANGLE ComboBox.l%-2, ComboBox.b%, ComboBox.r%-ComboBox.l%+2, ComboBox.t%-ComboBox.b%
      PROC_drawscrollbar(0, ScrlBarV{})
      PROC_drawscrollbar(1, ScrlBarH{})
      FOR I% = 0 TO 20
        IF TBenable&(I%) = FALSE THEN
          IF Darkmode% GCOL 2, COL_DISABLED ELSE GCOL 1, COL_DISABLED
          RECTANGLE FILL ToolPos%(I%), 2 * @vdu%!212 - BMPHEIGHT + 8, \
          \              BUTTONWIDTH, BUTTONHEIGHT
        ENDIF
        IF TBpressed&(I%) THEN
          IF Darkmode% GCOL 1, COL_PRESSED ELSE GCOL 2, COL_PRESSED
          RECTANGLE FILL ToolPos%(I%), 2 * @vdu%!212 - BMPHEIGHT + 8, \
          \              BUTTONWIDTH, BUTTONHEIGHT
          GCOL COL_SELECT
          RECTANGLE ToolPos%(I%), 2 * @vdu%!212 - BMPHEIGHT + 8, \
          \         BUTTONWIDTH, BUTTONHEIGHT
        ENDIF
      NEXT
      IF N% >= 0 IF W% IF H% THEN
        IF INKEY(-10) AND N% < NBUTTONS THEN
          IF Darkmode% GCOL 1, COL_PRESSED ELSE GCOL 2, COL_PRESSED
          RECTANGLE FILL X%, Y%, W%, H%
          RECTANGLE FILL X%, Y%, W%, H% TO X% + 2, Y% - 2
        ELSE
          GCOL 2, COL_HILITEAND
          RECTANGLE FILL X%, Y%, W%, H%
          GCOL 1, COL_HILITEOR
          RECTANGLE FILL X%, Y%, W%, H%
        ENDIF
        GCOL COL_SELECT
        IF N% < NBUTTONS + NMENUS RECTANGLE X%, Y%, W%, H%
      ENDIF
      *REFRESH ON
      *REFRESH
      ENDPROC
      
      DEF PROCrefresh(sh%, sv%, cx%, cy%, ax%, ay%, nl%)
      LOCAL B%, D%, H%, I%, J%, K%, L%, N%, P%, S%, X%, a$, b$, l$, r$
      LOCAL minx%, maxx%, miny%, maxy%, charx%, chary%, nrows%
      ON TIME LOCAL OFF
      
      minx% = EditRect.l%
      maxx% = EditRect.r%
      miny% = EditRect.b%
      maxy% = EditRect.t%
      charx% = 2 * @vdu%!216
      chary% = 2 * @vdu%!220
      nrows% = (maxy% - miny%) DIV chary% + 2
      
      IF cy%<>ay% THEN
        ax% = cx%
        L% = cy% : H% = ay%
        IF L% > H% SWAP L%,H%
      ELSE
        L% = -1
        H% = -1
      ENDIF
      
      S% = SelWord$ <> ""
      
      IF Unicode% @vdu.m.c& OR= &80 ELSE @vdu.m.c& AND= &7F
      VDU 5,24,minx%;miny%;maxx%;maxy%;23,16,64|
      GCOL 128 + COL_EDITPANE
      CLG : OFF
      GCOL 128 + COL_SELECT
      MOVE minx% + sh%, maxy% + sv% MOD chary%
      N% = sv% DIV chary%
      FOR I% = N% TO N% + nrows% - 1
        IF I% > nl% EXIT FOR
        D% = Indent%(I%)
        b$ = FNformat(Buffer$(I%), D%)
        X% = FNlen(b$)
        IF X% > MaxLen% MaxLen% = X%
        B% = 0 : K% = 1
        REPEAT
          J% = INSTR(b$, CHR$17, K%)
          IF J% THEN a$ = MID$(b$, K%, J%-K%) ELSE a$ = MID$(b$, K%)
          P% = FNlen(LEFT$(b$, K% - 1)) : K% = J% + 2
          IF B% THEN
            PROCbidi(a$, B%, I%, H%, L%, cx%-P%, cy%, ax%-P%, ay%)
          ELSE IF I% < H% IF I% >= L% THEN;
            PROCinvert(a$)
          ELSE
            IF I% = cy% THEN
              IF J%=0 PROCsplitx(a$, cx%-P%, l$, r$) ELSE PROCsplit(a$, cx%-P%, l$, r$)
              IF ax% < cx% THEN
                PROCsplit(l$, ax%-P%, l$, a$)
                IF S% THEN PROChiline(l$)
                PRINT l$;
                PROCinvert(a$)
              ELSE
                IF S% THEN PROChiline(l$)
                PRINT l$;
              ENDIF
              IF cx% >= P% THEN
                IF POS REM SDL thread sync
                @vdu.c.x% = @vdu.l.x%
                @vdu.c.y% = @vdu.l.y%
                ON
              ELSE
                cx% = P%
              ENDIF
              IF ax% > cx% THEN
                IF J%=0 PROCsplitx(r$, ax%-cx%, l$, a$) ELSE PROCsplit(r$, ax%-cx%, l$, a$)
                PROCinvert(l$)
                IF S% THEN PROChiline(a$)
                PRINT a$;
              ELSE
                IF S% THEN PROChiline(r$)
                PRINT r$;
              ENDIF
            ELSE
              IF S% THEN PROChiline(a$)
              PRINT a$;
            ENDIF
          ENDIF
          B% = ASCMID$(b$, J%+1, 1)
        UNTIL J% = 0
        PRINT
        PLOT 0,sh%,0
      NEXT
      
      IF POS REM SDL thread sync.
      VDU 24,0;0;@vdu%!208*2-2;@vdu%!212*2-2;4
      
      ScrlBarV.max% = nl% * chary%
      ScrlBarV.pos% = sv%
      ScrlBarV.page% = EditRect.t% - EditRect.b% - chary%
      ScrlBarH.max% = MaxLen% * charx%
      ScrlBarH.pos% = -sh%
      ScrlBarH.page% = EditRect.r% - EditRect.l%
      PROC_drawscrollbar(0, ScrlBarV{})
      PROC_drawscrollbar(1, ScrlBarH{})
      IF Dragging% = 2 PROChilite(IDVSCRL)
      IF Dragging% = 3 PROChilite(IDHSCRL)
      @vdu.m.c& OR= &80
      ENDPROC
      
      REM Output (possibly) bi-directional text:
      DEF PROCbidi(a$, S%, N%, H%, L%, cx%, cy%, ax%, ay%)
      IF N% <> cy% ax% = TRUE : cx% = TRUE
      IF N% < H% IF N% >= L% ax% = 0 : cx% = FNlen(a$)
      PROC_scriptsel(a$, Script$(S%), S% >> 4, ax%, cx%, Darkmode%)
      PROC_script("", "Latn", 0)
      ENDPROC
      
      REM Adjust indentation according to contents of program line:
      DEF PROCindent(f$, RETURN I%, RETURN M%)
      LOCAL C%, F%, L%, p%%
      
      IF f$="" THEN ENDPROC
      
      p%% = PTR(f$) + 3
      F% = 5 : REM initialise to "left" and "first"
      L% = 6 + 2 * I%
      
      CASE ?p%% OF
        WHEN &ED: I%-=1 : REM NEXT
        WHEN &FD: I%-=1 : REM UNTIL
        WHEN &CE: I%-=1 : REM ENDWHILE
        WHEN &CB: I%-=2 : REM ENDCASE
        WHEN &CD: I%-=1 : REM ENDIF
        WHEN &E3: I%+=1 : REM FOR
        WHEN &F5: I%+=1 : REM REPEAT
        WHEN &C7: I%+=1 : REM WHILE
        WHEN &C8: I%+=2 : REM CASE
        WHEN &28: F% OR= 8 : REM (
      ENDCASE
      
      WHILE ?p%% <> &D
        C% = ?p%%
        p%% += 1
        
        IF C% = &22 IF (F% AND &60) = FALSE F% EOR= &80
        
        IF F% AND &E0 THEN
          L% += 1
        ELSE
          CASE C% OF
            WHEN &8D: p%% += 3 : REM line number
            WHEN &2A: IF F% AND 1 F% OR= &50 : REM *
            WHEN &DC: IF F% AND 1 F% OR= &20 : REM DATA
            WHEN &F4: F% OR= &40 : REM REM
          ENDCASE
          IF C%<32 OR C%>127 L% += LENKeyWd$((C%+128)MOD256) ELSE L% += 1
        ENDIF
        
        IF C%<>32 F% AND= &FC : REM right mode, clear EXIT flag
        IF C%=&10 F% OR= 2    : REM set EXIT flag
        IF INSTR(Left$,CHR$C%) F% OR= &01 : REM left mode
        IF F% AND 8 IF C%=&29 F% AND= &F7 : REM end of label
        IF C%=&5C IF (F% AND &F4)=FALSE F% OR= &40 : REM \ comment
        F% AND= &FB : REM clear "first"
        
        IF (F% AND &F2) = FALSE THEN
          CASE ?p%% OF
            WHEN &ED: I%-=1 : REM NEXT
            WHEN &E3: I%+=1 : REM FOR
            WHEN &FD: I%-=1 : REM UNTIL
            WHEN &F5: I%+=1 : REM REPEAT
            WHEN &CE: I%-=1 : REM ENDWHILE
            WHEN &C7: I%+=1 : REM WHILE
            WHEN &C8: I%+=2 : REM CASE
          ENDCASE
        ENDIF
      ENDWHILE
      
      IF C% = &8C I%+=1 : REM THEN
      IF L% > M% M% = L%
      ENDPROC
      
      REM De-tokenise a program line and add syntax-colouring + indentation:
      DEF FNformat(f$, RETURN I%)
      LOCAL C%, F%, N%, S%, U%, p%%, a$, k$
      
      IF f$="" THEN = ""
      
      k$ = FNcolour(-1) : REM To force initial colour
      p%% = PTR(f$)
      N% = p%%?1 + 256*p%%?2 : p%% += 3
      IF N% THEN
        a$ = FNcolour(COL_LABEL) + RIGHT$("    " + STR$N%, 5) + " "
      ELSE
        a$ = FNcolour(COL_THEREST) + "      "
      ENDIF
      
      F% = 5 : REM initialise to "left" and "first"
      
      CASE ?p%% OF
        WHEN &ED: I%-=1 : REM NEXT
        WHEN &FD: I%-=1 : REM UNTIL
        WHEN &CE: I%-=1 : REM ENDWHILE
        WHEN &CB: I%-=2 : REM ENDCASE
        WHEN &CD: I%-=1 : REM ENDIF
        WHEN &8B: I%-=1 : REM ELSE
        WHEN &C9: I%-=1 : REM WHEN
        WHEN &CC: I%-=1 : REM OTHERWISE
      ENDCASE
      
      IF NOT Indentation% I% = 0
      a$ += STRING$(2*I%, " ")
      
      CASE ?p%% OF
        WHEN &E3: I%+=1 : REM FOR
        WHEN &F5: I%+=1 : REM REPEAT
        WHEN &C7: I%+=1 : REM WHILE
        WHEN &C8: I%+=2 : REM CASE
        WHEN &8B: I%+=1 : REM ELSE
        WHEN &C9: I%+=1 : REM WHEN
        WHEN &CC: I%+=1 : REM OTHERWISE
      ENDCASE
      
      IF ?p%% = ASC"(" THEN F% OR= 8 : a$ += FNcolour(COL_LABEL)
      
      WHILE ?p%% <> 13
        C% = ?p%%
        p%% += 1
        
        IF F% AND &C0 IF Unicode% THEN
          CASE TRUE OF
            WHEN C% >= &E0: U% = (C% << 12) AND &F000 OR (?p%% << 6) AND &FC0 OR p%%?1 AND &3F
            WHEN C% >= &C0: U% = (C% << 6) AND &07C0 OR ?p%% AND &3F
            OTHERWISE: U% = C%
          ENDCASE
          U% = Script&(U%) : IF U% = &FF U% = S%
        ELSE
          U% = 0
        ENDIF
        IF S% <> U% S% = U% : a$ += CHR$17 + CHR$S%
        
        IF C% = &22 IF (F% AND &60) = 0 F% EOR= &80 : IF F% AND &80 a$ += FNcolour(COL_STRING)
        
        IF F% AND &E8 THEN
          a$ += CHR$C%
        ELSE
          CASE C% OF
            WHEN &8D: REM line number
              N% = (((?p%% << 2) AND &C0) EOR p%%?1) + 256*(((?p%% << 4) AND &C0) EOR p%%?2)
              a$ += FNcolour(COL_LABEL) + STR$N% : p%% += 3
            WHEN &2A: IF F% AND 1 F% OR= &50 : REM *
            WHEN &DC: a$ += FNcolour(COL_KEYWD) : IF F% AND 1 F% OR= &20 : REM DATA
            WHEN &F4: a$ += FNcolour(COL_REMARK) : F% OR= &40 : REM REM
            WHEN &DD: a$ += FNcolour(COL_DEF) : REM DEF
            OTHERWISE:
              IF C%<&20 OR C%>=&80 a$ += FNcolour(COL_KEYWD)
          ENDCASE
          IF C%<&80 IF C%>=&20 THEN
            IF C%<>&20 IF C%<>&22 a$ += FNcolour(COL_THEREST)
            a$ += CHR$C%
          ELSE IF C%<>&8D THEN;
            IF Lowercase% k$ = FN_lower(KeyWd$(C% EOR &80)) ELSE k$ = KeyWd$(C% EOR &80)
            IF RIGHT$(k$) = "(" a$ += LEFT$(k$) + FNcolour(COL_THEREST) + "(" ELSE a$ += k$
          ENDIF
        ENDIF
        
        IF C%<>32 F% AND= &FC : REM right mode, clear EXIT flag
        IF C%=&10 F% OR= 2    : REM set EXIT flag
        IF INSTR(Left$,CHR$C%) F% OR= &01 : REM left mode
        IF F% AND 8 IF C%=ASC")" F% AND= &F7 : a$ += FNcolour(COL_THEREST)
        
        IF C%=&DC IF F% AND &20 a$ += FNcolour(COL_THEREST)
        IF C%=&5C IF (F% AND &F4)=0  F% OR= &40 : a$ += FNcolour(COL_REMARK)
        F% AND= &FB : REM clear "first"
        
        IF (F% AND &F2) = 0 THEN
          CASE ?p%% OF
            WHEN &ED: I%-=1 : REM NEXT
            WHEN &E3: I%+=1 : REM FOR
            WHEN &FD: I%-=1 : REM UNTIL
            WHEN &F5: I%+=1 : REM REPEAT
            WHEN &CE: I%-=1 : REM ENDWHILE
            WHEN &C7: I%+=1 : REM WHILE
            WHEN &C8: I%+=2 : REM CASE
          ENDCASE
        ENDIF
      ENDWHILE
      
      IF (F% AND &F2) = 0 IF C% = &8C I%+=1 : REM THEN
      
      WHILE RIGHT$(a$)=" " a$ = LEFT$(a$) : ENDWHILE
      = a$
      
      REM Insert a GCOL colour-change command if required:
      DEF FNcolour(C%)
      PRIVATE D%
      IF D% = C% THEN = ""
      D% = C%
      = CHR$18 + CHR$0 + CHR$D%
      
      REM Split a string, taking account of UTF-8 and control characters:
      DEF PROCsplit(a$, N%, RETURN l$, RETURN r$)
      LOCAL I%, l%%, p%%
      p%% = PTR(a$) : l%% = p%% + LENa$
      WHILE I% < N% AND p%% < l%%
        CASE TRUE OF
          WHEN ?p%%<&20: p%% += 1
          WHEN ?p%%>&BF: I% += 1 : IF Unicode% p%% += (?p%% >>> 5) - 4 ELSE p%% += 1
          OTHERWISE:     I% += 1 : p%% += 1
        ENDCASE
      ENDWHILE
      l%% = PTR(a$)
      l$ = LEFT$(a$, p%%-l%%)
      r$ = MID$(a$, p%%-l%% + 1)
      ENDPROC
      
      REM Split and if necessary extend
      DEF PROCsplitx(a$, N%, RETURN l$, RETURN r$)
      LOCAL I%, l%%, p%%
      p%% = PTR(a$) : l%% = p%% + LENa$
      WHILE I% < N% AND p%% < l%%
        CASE TRUE OF
          WHEN ?p%%<&20: p%% += 1
          WHEN ?p%%>&BF: I% += 1 : IF Unicode% p%% += (?p%% >>> 5) - 4 ELSE p%% += 1
          OTHERWISE:     I% += 1 : p%% += 1
        ENDCASE
      ENDWHILE
      l%% = PTR(a$)
      l$ = LEFT$(a$, p%%-l%%) + STRING$(N%-I%, " ")
      r$ = MID$(a$, p%%-l%% + 1)
      ENDPROC
      
      DEF PROCinvert(a$)
      IF POS REM SDL thread sync.
      LOCAL C%, F%, X%, Y% : C% = @vdu%!64
      F% = FNinstrr(a$, CHR$18, 0)
      IF F% C% = C% AND &FFFF00FF OR (ASCMID$(a$, F%+2) << 8)
      a$ = FNstrip(a$)
      IF a$="" ENDPROC
      X% = FN_stringwidth(a$)
      Y% = 2 * @vdu%!220
      GCOL 128 + COL_SELECT
      GCOL COL_EDITPANE
      PLOT 99,X%,-Y%
      PLOT 0,-X%,Y%
      PRINT a$;
      IF POS REM SDL thread sync.
      @vdu%!64 = C%
      ENDPROC
      
      DEF PROChiword(a$)
      LOCAL X%, Y%
      X% = FN_stringwidth(a$)
      Y% = 2 * @vdu%!220
      IF Darkmode% GCOL 1, 128 + COL_HILITEOR  ELSE GCOL 2, 128 + COL_HILITEAND
      PLOT 99,X%,-Y%
      PLOT 0,-X%,Y%
      PRINT a$;
      GCOL 128 + COL_EDITPANE
      ENDPROC
      
      DEF PROChiline(RETURN a$)
      LOCAL I%, L%
      L% = LEN(SelWord$)
      REPEAT
        I% = INSTR(a$, SelWord$, I%+1)
        IF I% = FALSE EXIT REPEAT
        IF INSTR(Valid$, MID$(a$,I%-1,1)) = FALSE THEN
          PRINT LEFT$(a$, I%-1);
          PROChiword(MID$(a$, I%, L%))
          a$ = MID$(a$, I% + L%)
          I% = 0
        ENDIF
      UNTIL FALSE
      ENDPROC
      
      REM Strip all control characters (<&20) from a string:
      DEF FNstrip(a$)
      LOCAL l%%, p%%, s$
      p%% = PTR(a$) : l%% = p%% + LENa$
      WHILE p%% < l%%
        IF ?p%%>=&20 s$ += CHR$?p%%
        p%% += 1
      ENDWHILE
      = s$
      
      REM Return string length, taking acount of UTF-8 and control chars:
      DEF FNlen(a$)
      LOCAL I%, p%%
      IF a$ = "" THEN = 0
      FOR p%% = PTR(a$) TO PTR(a$) + LENa$ - 1
        IF ?p%% >= &20 THEN
          IF NOT Unicode% I% += 1 ELSE IF ?p%% AND &C0 EOR &80 I% += 1
        ENDIF
      NEXT
      = I%
      
      REM Check whether a quoted string (if any) is probably ANSI or UTF-8:
      DEF FNansi_or_utf8(a$)
      LOCAL Q%, p%%
      Q% = INSTR(a$, CHR$&22, 4)
      IF Q% = 0 THEN = 0
      REPEAT
        p%% = PTR(a$) + Q% - 1
        REPEAT
          p%% += 1
          IF ?p%% = &D THEN = 0
          IF ?p%% >= &C0 IF p%%?1 >= &80 IF p%%?1 < &C0 THEN = 2 : REM UTF-8
          IF ?p%% >= &80 THEN = 1 : REM ANSI
        UNTIL ?p%% = &22
        Q% = INSTR(a$, CHR$&22, p%% - PTR(a$) + 2)
      UNTIL Q% = 0
      = 0
      
      REM Tokenise a program line:
      DEF FNtokenise(a$)
      IF Lowercase% THEN *lowercase
      LOCAL I%,n,t$
      n = VAL(a$)
      IF n < 0 OR n > 65535 THEN
        n = 0
        WHILE ASCa$=&20 a$ = MID$(a$,2) : ENDWHILE
      ELSE
        WHILE ASCa$=&20 OR ASCa$>=&30 AND ASCa$<=&39 a$ = MID$(a$,2) : ENDWHILE
      ENDIF
      WHILE RIGHT$(a$) = " " a$ = LEFT$(a$) : ENDWHILE
      I% = FNinstrq(a$, "\", 2)
      IF I% t$ = MID$(a$,I%+1) : a$ = LEFT$(a$,I%)
      IF NOT Abbrev% THEN
        REPEAT
          I% = INSTR(a$, ".")
          IF I% MID$(a$,I%,1) = CHR$17
        UNTIL I% = 0
      ENDIF
      REPEAT
        I% = INSTR(a$, "\")
        IF I% MID$(a$,I%,1) = CHR$18
      UNTIL I% = 0
      IF EVAL("1RECTANGLERECTANGLE:"+a$) a$ = $(Accs%%+4)
      REPEAT
        I% = INSTR(a$, CHR$17)
        IF I% MID$(a$,I%,1) = "."
      UNTIL I% = 0
      REPEAT
        I% = INSTR(a$, CHR$18)
        IF I% MID$(a$,I%,1) = "\"
      UNTIL I% = 0
      a$ += t$
      *lowercase off
      IF LENa$ > 251 THEN
        PROCmessagebox("SDLIDE", "Line too long: truncated", 0)
        a$ = LEFT$(a$,251)
      ENDIF
      = CHR$(LENa$+4)+CHR$(n MOD256)+CHR$(n DIV256)+a$+CHR$&D
      
      REM Reformat an edited program line:
      DEF PROCreformat(a$, RETURN X%, Y%, f$(), i%(), B%)
      LOCAL D%, F%, I%, L%, M%, N%, O%
      L% = i%(Y%)
      a$ = FNstrip(a$)
      IF MID$(a$, X%-4, 5) = "COLOR" D% = LEN(a$) - X% + 1
      IF Lowercase% IF MID$(a$, X%-4, 5) = "color" D% = LEN(a$) - X% + 1
      IF Abbrev% IF MID$(a$, X%, 1) = "." D% = LEN(a$) - X% + 1
      F% = 5 - (INSTR("0123456789", MID$(a$, 6, 1)) <> 0)
      REPEAT M% += 1 : UNTIL MID$(a$, M%, 1) <> " " : O% = M%
      IF O% < 7 IF X% > F% IF VAL(a$)<>0 M% = 5 : REPEAT M% += 1 : UNTIL MID$(a$, M%, 1) <> " "
      f$(Y%) = FNtokenise(a$)
      a$ = FNstrip(FNformat(f$(Y%), L%))
      REPEAT N% += 1 : UNTIL MID$(a$, N%, 1) <> " "
      IF O% < 7 IF X% > F% IF VAL(a$)<>0 N% = 5 : REPEAT N% += 1 : UNTIL MID$(a$, N%, 1) <> " "
      IF B% = FALSE OR M% <> N% - 1 OR M% < 6 X% += N% - M% : IF X% < 0 X% = 0
      IF D% X% += LEN(a$) - X% + 1 - D%
      L% -= i%(Y%+1)
      IF L% = 0 ENDPROC
      FOR I% = Y%+1 TO DIM(i%(),1)
        i%(I%) += L%
      NEXT
      ENDPROC
      
      DEF PROCupdaterecent(file$)
      LOCAL I%, J%
      IF file$ = Recent$(1) THEN ENDPROC
      FOR I% = 2 TO 8
        IF file$ = Recent$(I%) THEN
          FOR J% = I% TO 8
            Recent$(J%) = Recent$(J%+1)
          NEXT
          Recent$(9) = ""
        ENDIF
      NEXT
      FOR I% = 9 TO 2 STEP -1
        Recent$(I%) = Recent$(I%-1)
      NEXT
      Recent$(1) = file$
      FOR I% = 1 TO 9
        FileMenu$(I%+10) = "&" + STR$(I%) + " " + FNnopath(Recent$(I%))
      NEXT
      ENDPROC
      
      REM Draw statusbar:
      REM Setting the second parameter to TRUE forces the font to be changed;
      REM don't do this frequently since it flushes the font cache and is slow.
      DEF PROCdrawstatusbar(N%, F%, force%)
      LOCAL S%, X%
      PRIVATE oldn%, olds%, oldx%, oldy%, oldo%, oldu%
      
      S% = SUMLEN(Buffer$()) + 3
      IF oldn% = N% IF olds% = S% IF oldx% = CaretX% IF oldy% = CaretY% \
      \  IF oldo% = Overtype% IF oldu% = Unicode% IF NOT force% ENDPROC
      oldn% = N% : olds% = S% : oldx% = CaretX% : oldy% = CaretY%
      oldo% = Overtype% : oldu% = Unicode%
      
      IF F% OSCLI "FONT " + GUIFont$ : VDU 5
      
      *REFRESH OFF
      GCOL COL_GUIBKGD
      RECTANGLE FILL 0, 0, @vdu%!208 * 2, STATUSBARHEIGHT - 2
      GCOL COL_GUITEXT
      MOVE 10, STATUSBARHEIGHT DIV 2 + @vdu%!220
      
      CASE TRUE OF
        WHEN N% = 0:
          X% = @vdu%!208 * 2
          PRINT Title$ + ", © R.T.Russell " + Year$ + ".  Press F1 for Help";
          PROCcentretext(X%, FN_stringwidth(" OVR "), LEFT$("OVR", oldo%))
          PROCcentretext(X%, FN_stringwidth(" 999,99999 "), STR$(oldx%)+","+STR$(oldy%))
          PROCcentretext(X%, FN_stringwidth(" 999999 "), STR$(olds%))
          PROCcentretext(X%, FN_stringwidth(" Unicode "), MID$("UnicodeANSI", 8+7*oldu%, 7))
        WHEN N% <= DIM(MenuHelp$(),1):
          PRINT MenuHelp$(N%);
        WHEN N% = 400:
          PRINT "Comparing... please wait"
        WHEN N% = 401:
          PRINT "Press F8 for next difference, F7 for previous difference. " + \
          \     "Press Esc or click here to dismiss."
        WHEN N% >= 391:
          PRINT "Run " + Addin$(N% MOD 10);
        WHEN N% >= 381:
          PRINT Recent$(N% MOD 10);
      ENDCASE
      *REFRESH
      *REFRESH ON
      
      IF F% THEN
        OSCLI "FONT " + EditFont$
        VDU 23,0,10,0,0;0;0; : REM Set start line
        VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
        VDU 23,0,18,2,0;0;0; : REM Set cursor width
        VDU 4
      ENDIF
      Refresh% = TRUE : REM To reset caret
      ENDPROC
      
      DEF PROCcentretext(RETURN X%, W%, a$)
      LOCAL L%
      WHILE ASCa$ = &20 a$ = MID$(a$,2) : ENDWHILE
      X% -= W%
      GCOL COL_BORDERS
      LINE X%, 0, X%, STATUSBARHEIGHT
      L% = FN_stringwidth(a$)
      PLOT 0, (W% - L%) DIV 2, @vdu%!220 - STATUSBARHEIGHT DIV 2
      GCOL COL_GUITEXT : PRINT a$;
      PLOT 0, -(W% - L%) DIV 2, STATUSBARHEIGHT DIV 2 - @vdu%!220
      ENDPROC
      
      DEF PROCdrawall(W%, H%)
      REM Clear screen:
      COLOR 128 + COL_GUIBKGD
      CLS
      VDU 5
      
      REM Define edit viewport:
      EditRect.l% = BREAKPTBARWIDTH
      EditRect.t% = 2 * H% - BMPHEIGHT - 4
      EditRect.r% = 2 * W% - SCROLLBARSIZE - 2
      EditRect.b% = STATUSBARHEIGHT + SCROLLBARSIZE
      
      REM Breakpoint bar:
      BrkPtBar.l% = 0
      BrkPtBar.t% = EditRect.t%
      BrkPtBar.r% = EditRect.l% - 4
      BrkPtBar.b% = EditRect.b%
      
      REM List DEFs combobox:
      ComboBox.l% = ToolPos%(NBUTTONS) + 10
      ComboBox.t% = 2 * H% - (MENUBARHEIGHT + BMPHEIGHT) DIV 2 + @vdu%!220
      ComboBox.r% = 2 * W% - GAPCOMBO
      ComboBox.b% = 2 * H% - (MENUBARHEIGHT + BMPHEIGHT) DIV 2 - @vdu%!220
      IF (ComboBox.r% - ComboBox.l%) < MINCOMBO ComboBox.r% = ComboBox.l% + MINCOMBO
      
      REM Scrollbars:
      ScrlBarH.l% = EditRect.l% + SCROLLBARSIZE - 6
      ScrlBarH.r% = EditRect.r% - SCROLLBARSIZE + 6
      ScrlBarH.t% = STATUSBARHEIGHT + SCROLLBARSIZE - 4
      ScrlBarH.b% = STATUSBARHEIGHT + 2
      ScrlBarV.l% = 2 * W% - SCROLLBARSIZE + 2
      ScrlBarV.r% = 2 * (W% - 1)
      ScrlBarV.t% = EditRect.t% - SCROLLBARSIZE + 6
      ScrlBarV.b% = EditRect.b% + SCROLLBARSIZE - 6
      
      REM Draw borders:
      GCOL COL_BORDERS
      LINE EditRect.l%-2,EditRect.t%+2,EditRect.l%-2,STATUSBARHEIGHT
      LINE EditRect.l%-2,EditRect.t%+2,2*W%-2,EditRect.t%+2
      LINE EditRect.l%-2,STATUSBARHEIGHT,2*W%-2,STATUSBARHEIGHT
      
      LINE EditRect.r%+2,EditRect.t%+2,EditRect.r%+2,STATUSBARHEIGHT
      LINE EditRect.l%-2,EditRect.b%-2,2*W%-2,EditRect.b%-2
      LINE EditRect.l%-2,2*H%-MENUBARHEIGHT+2,2*W%-2,2*H%-MENUBARHEIGHT+2
      
      PROCdrawstatusbar(0, TRUE, TRUE)
      PROCtimer(TRUE)
      ENDPROC
      
      REM Search, skipping quoted text:
      DEF FNinstrq(A$, B$, S%)
      LOCAL I%, Q%
      REPEAT
        I% = INSTR(A$, B$, S%)
        Q% = INSTR(A$, """", S%)
        IF Q%=0 OR I%<Q% THEN = I%
        S% = INSTR(A$, """", Q%+1)+1
      UNTIL S%=1
      = 0
      
      REM Search backwards from end of string:
      DEF FNinstrr(A$, B$, S%)
      LOCAL O%,P%
      IF S%=0 S% = LEN(A$)
      REPEAT
        O% = P%
        P% = INSTR(A$, B$, P%+1)
      UNTIL P% = 0 OR P% > S%
      = O%
      
      DEF FNoktoditch
      LOCAL R%
      IF NOT Unsaved% THEN = TRUE
      R% = FNmessagebox("SDLIDE", "Save changes?", MB_ICONQUESTION + MB_YESNOCANCEL)
      IF R% = IDYES IF FNsave PROCunchanged : = TRUE
      IF R% = IDNO PROCunchanged : = TRUE
      = FALSE
      
      DEF PROCunchanged
      Unsaved% = FALSE
      Changed% = FALSE
      ENDPROC
      
      DEF PROCpointtochar(RETURN X%, RETURN Y%)
      LOCAL B%, C%, H%, I%, J%, K%, P%, W%, a$, b$, l$, r$
      Y% = (ScrollV% + EditRect.t% - Y%) DIV (2 * @vdu%!220)
      X% -= EditRect.l% + ScrollH% - @vdu%!216
      IF Y% < 0 Y% = 0
      IF nLines% = 0 X% = 0 : Y% = 0 : ENDPROC
      I% = Indent%(Y%)
      b$ = FNformat(Buffer$(Y%), I%)
      IF Unicode% @vdu.m.c& OR= &80 ELSE @vdu.m.c& AND= &7F
      B% = 0 : K% = 1
      REPEAT
        J% = INSTR(b$, CHR$17, K%)
        IF J% THEN a$ = MID$(b$, K%, J%-K%) ELSE a$ = MID$(b$, K%)
        P% = FNlen(LEFT$(b$, K% - 1)) : K% = J% + 2
        IF B% PROC_script("", Script$(B%), B% >> 4)
        X% -= W% : W% = WIDTH(a$)
        IF J% = 0 OR W% > X% EXIT REPEAT
        B% = ASCMID$(b$, J%+1, 1)
      UNTIL FALSE
      IF B% AND &10 X% = W% - X% : P% += 1 : REM RTL
      C% = 1 : WHILE C% <= FNlen(a$) C% *= 2 : ENDWHILE
      REPEAT
        C% DIV= 2
        PROCsplitx(a$, H% + C%, l$, r$)
        IF X% > WIDTH(l$) H% += C%
      UNTIL C% = 0
      X% = H% + P%
      @vdu.m.c& OR= &80
      PROC_script("", "Latn", 0)
      VDU 4
      ENDPROC
      
      DEF FNchop(a%(), S%)
      LOCAL B%, H%, T%
      T% = DIM(a%(),1)
      H% = 2
      WHILE H%<T% H% *= 2:ENDWHILE
      H% /= 2
      REPEAT
        IF (B%+H%)<=T% IF S%>=a%(B%+H%) B% += H%
        H% /= 2
      UNTIL H%=0
      = B%
      
      DEF FNchops(a$(), s$)
      LOCAL B%, H%, L%, P%, a$
      H% = DIM(a$(),1)
      REPEAT
        B% = (L% + H%) DIV 2 : a$ = a$(B%) : P% = B%
        WHILE ASCa$ = 9 : P% -= 1 : a$ = a$(P%) : ENDWHILE
        IF a$ <> "" IF s$ > a$ L% = B% ELSE H% = B%
      UNTIL (H% - L%) <= 1
      = L%
      
      DEF PROCcursor(C%)
      PRIVATE O%
      IF C%=O% ENDPROC ELSE O% = C%
      LOCAL B%, X%, Y%
      MOUSE ON C%
      MOUSE X%, Y%, B%
      MOUSE TO X%, Y%
      ENDPROC
      
      DEF FNhotspot(X%, Y%)
      LOCAL B%
      
      B% = FN_sbhotspot(0, ScrlBarV{}, X%, Y%)
      IF B% <> -1 THEN = IDVSCRL - 2 + B%
      B% = FN_sbhotspot(1, ScrlBarH{}, X%, Y%)
      IF B% <> -1 THEN = IDHSCRL - 2 + B%
      
      CASE TRUE OF
        WHEN FN_ptinrect(X%, Y%, ComboBox{}):
          B% = IDCOMBO
        WHEN Y% < 2*@vdu%!212 - BMPHEIGHT OR Y% >= 2*(@vdu%!212 - 1) OR X% <= 0:
          B% = -1
        WHEN Y% > 2*@vdu%!212 - MENUBARHEIGHT:
          B% = 0
          WHILE X% > MenuPos%(B%+1) AND B% < NMENUS-1 : B% += 1 : ENDWHILE
          IF X% > MenuPos%(NMENUS) THEN
            B% = -1
          ELSE
            B% += IDMENU1
          ENDIF
        WHEN X% > 0:
          B% = 0
          WHILE X% > ToolPos%(B%+1) AND B% < NBUTTONS-1 : B% += 1 : ENDWHILE
          IF X% > ToolPos%(NBUTTONS) THEN
            B% = -1
          ELSE
            IF TBenable&(B%) = FALSE B% = -1
          ENDIF
      ENDCASE
      = B%
      
      DEF PROChotspot(N%, RETURN X%, RETURN Y%, RETURN W%, RETURN H%)
      CASE N% OF
        WHEN -1:
          Pressed% = FALSE
        WHEN IDMENU1,IDMENU2,IDMENU3,IDMENU4,IDMENU5,IDMENU6:
          X% = MenuPos%(N%-IDMENU1)
          Y% = 2 * @vdu%!212 - MENUBARHEIGHT + 8
          W% = MenuPos%(N%+1-IDMENU1) - X%
          H% = MENUBARHEIGHT - 16
        WHEN IDSCRLD,IDPAGED,IDVSCRL,IDPAGEU,IDSCRLU:
          PROC_sbhotspot(N% - IDSCRLD, ScrlBarV{}, X%, Y%, W%, H%)
        WHEN IDSCRLL,IDPAGEL,IDHSCRL,IDPAGER,IDSCRLR:
          PROC_sbhotspot(N% - IDSCRLD, ScrlBarH{}, X%, Y%, W%, H%)
        WHEN IDCOMBO:
          X% = ComboBox.l%
          Y% = ComboBox.b% + 2
          W% = ComboBox.r% - ComboBox.l% - 2
          H% = ComboBox.t% - ComboBox.b% - 4
        OTHERWISE:
          X% = ToolPos%(N%)
          Y% = 2 * @vdu%!212 - BMPHEIGHT + 8
          W% = BUTTONWIDTH
          H% = BUTTONHEIGHT
      ENDCASE
      ENDPROC
      
      DEF PROCcompare(file$)
      LOCAL H%, I%, L%, N%, R%, W%, X%, Y%, d%, k%, new%%, start%%, link%%
      LOCAL col%, file%, lower%, upper%, nline%, oline%, origin%, maxlines%, row%
      LOCAL D$, new$, old$, script%%(), last_d%(), ntotal%, ototal%, format%
      LOCAL ahead{}, behind{}, ep{}, hash{}, new{}, click%(), result$()
      PRIVATE edit{} : DIM click%(2)
      
      ON SYS LOCAL OFF
      ON TIME LOCAL OFF
      ON MOVE LOCAL Resized% OR= (@msg% == WM_SIZE) : RETURN
      ON MOUSE LOCAL click%() = @msg%,@wparam%,@lparam% : RETURN
      
      REM This program compares hashes rather than the source data.  A
      REM 'collision' will result in a false match, but that would only
      REM alter the final result if it created or extended a 'diagonal'
      REM in the 'virtual matrix', which is unlikely.
      
      file% = OPENIN(file$)
      IF file% = 0 THEN
        PROCmessagebox("SDLIDE", "Couldn't open file '" + file$ + "'", 0)
        ENDPROC
      ENDIF
      
      REM Inform user of a possible wait:
      PROCdrawstatusbar(400, TRUE, TRUE)
      
      REM Count lines in 'new' version:
      ntotal% = nLines%
      
      REM Count lines in 'old' version:
      ototal% = 0
      format% = 0 : REM .BBC (tokenised)
      REPEAT
        IF format% = 0 THEN
          N% = BGET#file%
          L% = BGET#file%
          H% = BGET#file%
        ENDIF
        INPUT #file%, D$
        IF N% ototal% += 1 : IF N% <> LEN(D$)+4 format% = 1 : REM .BAS (ASCII)
        IF format% R% = BGET#file%
      UNTIL EOF#file% OR N%=0
      PTR#file% = 0
      
      REM Allocate arrays:
      DIM hash{new%(ntotal%), old%(ototal%)}
      
      REM Build hash table for earlier (file) program:
      FOR I% = 0 TO ototal%-1
        hash.old%(I%) = FNhash(FNtok(file%, format%))
      NEXT
      PTR#file% = 0
      
      REM Build hash table for current (IDE) program:
      FOR I% = 0 TO ntotal%-1
        hash.new%(I%) = FNhash(LEFT$(MID$(Buffer$(I%), 4)))
      NEXT
      
      REM Walk the virtual matrix:
      DIM edit{link%%, line1%, line2%, op&}
      DIM new{}=edit{}, ep{}=edit{}, behind{}=edit{}, ahead{}=edit{}
      
      IF ototal%>ntotal% maxlines% = ototal% ELSE maxlines% = ntotal%
      origin% = maxlines%
      DIM last_d%(2*maxlines%+2), script%%(2*maxlines%+2)
      
      REM Skip Matching lines at start of files:
      row% = 0
      WHILE hash.old%(row%) = hash.new%(row%)
        row% += 1
        IF row% >= ototal% OR row% >= ntotal% EXIT WHILE
      ENDWHILE
      last_d%(origin%+1) = row%
      IF row% = ototal% lower% = origin% + 1 ELSE lower% = origin% - 1
      IF row% = ntotal% upper% = origin% - 1 ELSE upper% = origin% + 1
      IF lower% > upper% THEN
        CLOSE #file%
        PROCmessagebox("SDLIDE", "The programs are identical", 0)
        ENDPROC
      ENDIF
      
      start%% = 0
      REM For each value of the edit distance:
      FOR d% = 1 TO ototal% + ntotal%
        IF INKEY(0) = 27 ENDPROC
        REM For each relevant diagonal:
        FOR k% = lower% TO upper% STEP 2
          REM Get space for the next edit instruction:
          SYS FNmalloc, DIM(edit{}) TO new%%
          IF NOT BB4W% IF @platform% AND &40 ELSE new%% = !^new%%
          PROC_setptr(new{}, new%%)
          REM Find a d on diagonal k:
          IF k% = origin%-d% OR k% <> origin%+d% AND last_d%(k%+2) >= last_d%(k%) THEN
            row% = last_d%(k%+2) + 1
            new.link%% = script%%(k%+2)
            new.op& = OP_DELETE
          ELSE
            row% = last_d%(k%)
            new.link%% = script%%(k%)
            new.op& = OP_INSERT
          ENDIF
          REM Code common to the two cases:
          col% = row% + k% - origin%
          new.line1% = row%
          new.line2% = col%
          script%%(k%+1) = new%%
          
          REM Slide down the diagonal:
          IF row%<ototal% IF col%<ntotal% THEN
            WHILE hash.old%(row%)=hash.new%(col%)
              row% += 1
              col% += 1
              IF row%>=ototal% OR col%>=ntotal% EXIT WHILE
            ENDWHILE
          ENDIF
          last_d%(k%+1) = row%
          
          REM Hit southeast corner, have the answer:
          IF row% = ototal% IF col% = ntotal% start%% = script%%(k%+1) : EXIT FOR d%
          REM Hit last row; don't look to the left:
          IF row% = ototal% lower% = k%+2
          REM Hit last column; don't look to the right:
          IF col% = ntotal% upper% = k%-2
          
        NEXT k%
        lower% -= 1
        upper% += 1
      NEXT d%
      
      REM Reverse the pointers:
      PROC_setptr(ahead{}, start%%)
      PROC_setptr(ep{}, 0)
      WHILE ahead{}
        PROC_setptr(behind{}, ep{})
        PROC_setptr(ep{}, ahead{})
        PROC_setptr(ahead{}, ahead.link%%)
        ep.link%% = behind{}
      ENDWHILE
      
      REM List the differences:
      DIM result$(ototal% + ntotal%)
      N% = 1
      
      oline% = 0
      nline% = 0
      WHILE ep{}
        
        WHILE nline% < (ep.line2%-1) OR oline% < (ep.line1%-1)
          old$ = FNasc(file%,format%)
          L% = nline% : I% = 0 : new$ = FNstrip(FNformat(Buffer$(L%), I%))
          result$(N%) = CHR$18+CHR$0+CHR$0+"= "+new$
          N% += 1
          oline% += 1
          nline% += 1
        ENDWHILE
        
        IF ep.op& = OP_DELETE THEN
          old$ = FNasc(file%,format%)
          result$(N%) = CHR$18+CHR$0+CHR$3+"< "+old$
          N% += 1
          oline% = ep.line1%
        ELSE
          L% = nline% : I% = 0 : new$ = FNstrip(FNformat(Buffer$(L%), I%))
          result$(N%) = CHR$18+CHR$0+CHR$4+"> "+new$
          N% += 1
          nline% = ep.line2%
        ENDIF
        
        link%% = ep{}
        PROC_setptr(ep{}, ep.link%%)
        IF link%% < PAGE OR link%% > HIMEM SYS FNfree, link%%
      ENDWHILE
      
      WHILE nline% < ntotal% OR oline% < ototal%
        L% = nline% : I% = 0 : new$ = FNstrip(FNformat(Buffer$(L%), I%))
        result$(N%) = CHR$18+CHR$0+CHR$0+"= "+new$
        N% += 1
        oline% += 1
        nline% += 1
      ENDWHILE
      CLOSE #file%
      
      Resized% = TRUE
      PROCdrawstatusbar(401, TRUE, TRUE)
      PROC_setlistboxarray(Compare%, 400, result$(), N%)
      FOR d% = 1 TO N%
        IF MID$(result$(d%),4,1) <> "=" THEN
          PROC_setlistboxselect(Compare%, 400, d%)
          EXIT FOR
        ENDIF
      NEXT
      IF FN_polldialog(Compare%, 9, click%())
      OFF
      REPEAT
        k% = INKEY(4)
        CASE k% OF
          WHEN 27: EXIT REPEAT
          WHEN 151: IF d% > 1  REPEAT d% -= 1 UNTIL MID$(result$(d%),4,1) <> "=" OR d% = 1
            PROC_setlistboxselect(Compare%, 400, d%)
            PROC_refreshdialog(Compare%)
          WHEN 152: IF d% < N% REPEAT d% += 1 UNTIL MID$(result$(d%),4,1) <> "=" OR d% = N%
            PROC_setlistboxselect(Compare%, 400, d%)
            PROC_refreshdialog(Compare%)
        ENDCASE
        IF Resized% THEN
          Resized% = FALSE
          VDU 26 : IF POS REM SDL thread sync
          PROCdrawall(@vdu%!208, @vdu%!212)
          OSCLI "GSAVE """ + @tmp$ + "bbc" + Session$ + ".tmp.bmp"""
          PROCdrawstatusbar(401, TRUE, TRUE)
          PROC_setdlgrect(Compare%, 0, @vdu%!212 * 2 - 2, 0, 0)
          PROC_getdlgitemrect(Compare%, 400, X%, Y%, W%, H%)
          PROC_setdlgitemrect(Compare%, 400, X%, Y%, \
          \                   2*@vdu%!208 - BREAKPTBARWIDTH, \
          \                   2*@vdu%!212 - STATUSBARHEIGHT - BMPHEIGHT)
          PROC_refreshdialog(Compare%)
        ENDIF
      UNTIL FN_polldialog(Compare%, k%, click%()) = TRUE
      ON
      
      OSCLI "DISPLAY """ + @tmp$ + "bbc" + Session$ + ".tmp.bmp"""
      VDU 24,0;0;@vdu%!208*2-2;@vdu%!212*2-2;
      PROCdrawstatusbar(0, TRUE, TRUE)
      
      OSCLI "FONT " + EditFont$
      VDU 23,0,10,0,0;0;0; : REM Set start line
      VDU 23,0,11,@vdu%!220,0;0;0; : REM Set end line
      VDU 23,0,18,2,0;0;0; : REM Set cursor width
      Refresh% = TRUE
      ENDPROC
      
      DEF FNhash(a$)
      LOCAL H%,p%%
      IF a$="" THEN = 0
      FOR p%% = PTR(a$) TO PTR(a$) + LENa$ - 1
        H% = H% * &21 AND &7FFFFFFF EOR ?p%%
      NEXT
      = H%
      
      DEF FNtok(F%,T%)
      LOCAL a$,I%
      IF T% THEN
        INPUT #F%,a$
        IF ASCa$ = &A a$ = MID$(a$,2)
        a$ = LEFT$(MID$(FNtokenise(a$),4))
      ELSE
        IF BGET#F% I% = BGET#F%+256*BGET#F%
        INPUT #F%,a$
      ENDIF
      = a$
      
      DEF FNasc(F%,T%)
      LOCAL a$,I%
      IF T% THEN
        INPUT #F%,a$
        IF ASCa$ = &A a$ = MID$(a$,2)
      ELSE
        a$ = CHR$BGET#F% + CHR$BGET#F% + CHR$BGET#F% + GET$#F% TO &D + CHR$&D
        a$ = FNstrip(FNformat(a$,I%))
      ENDIF
      = a$
      
      DEF FNdark
      LOCAL s$
      IF Darkmode% s$ = " -dark"
      IF GUIscale > 2 s$ += " -scale " + STR$GUIscale
      = s$
      
      DEF FNmalloc
      IF NOT BB4W% THEN = SYS("SDL_malloc")
      PRIVATE malloc%
      IF malloc% THEN = malloc%
      LOCAL msvcrt%
      SYS "LoadLibraryA", "MSVCRT.DLL" TO msvcrt%
      SYS "GetProcAddress", msvcrt%, "malloc" TO malloc%
      = malloc%
      
      DEF FNfree
      IF NOT BB4W% THEN = SYS("SDL_free")
      PRIVATE free%
      IF free% THEN = free%
      LOCAL msvcrt%
      SYS "LoadLibraryA", "MSVCRT.DLL" TO msvcrt%
      SYS "GetProcAddress", msvcrt%, "free" TO free%
      = free%
      
      DEF PROCputkey(K%)
      LOCAL A%, B%
      B% = @vdu%?203 : A% = (B% + 1) AND &FF
      IF NOT BB4W% IF @platform% AND &40 THEN
        IF A% <> @vdu%?204 ?(]428 + B%) = K% : @vdu%?203 = A%
      ELSE
        IF A% <> @vdu%?204 ?(!428 + B%) = K% : @vdu%?203 = A%
      ENDIF
      ENDPROC
      
      DEF FNgetINIstring(f$, k$, d$)
      LOCAL F%, I%, a$
      F% = OPENIN(f$)
      IF F% = 0 THEN = d$
      k$ = FN_lower(FN_trim(k$))
      WHILE NOT EOF#F%
        a$ = GET$#F%
        I% = INSTR(a$, "=")
        IF I% IF FN_lower(FN_trim(LEFT$(a$,I%-1))) = k$ d$ = FN_trim(MID$(a$,I%+1)) : EXIT WHILE
      ENDWHILE
      CLOSE #F%
      IF ASC(d$) = &22 IF RIGHT$(d$) = """" d$ = EVAL(d$)
      = d$
      
      DEF PROCputINIstring(f$, k$, v$)
      LOCAL I%, P%, a$, d$
      PRIVATE F% : IF F% ENDPROC
      F% = OPENUP(f$)
      IF F% = 0 F% = OPENOUT(f$)
      IF F% = 0 ERROR 100, "Couldn't create INI file"
      k$ = FN_lower(FN_trim(k$))
      WHILE NOT EOF#F%
        P% = PTR#F%
        a$ = GET$#F%
        I% = INSTR(a$, "=")
        IF I% IF FN_lower(FN_trim(LEFT$(a$,I%-1))) = k$ d$ = MID$(a$,I%+1) : EXIT WHILE
        IF a$ = ""  THEN PTR#F% = P% : IF BGET#F% = 0 THEN PTR#F% = P% : EXIT WHILE
      ENDWHILE
      IF d$ <> v$ THEN
        a$ = GET$#F% TO 0
        PTR#F% = P%
        BPUT #F%, k$ + "=" + v$
        BPUT #F%, a$ + CHR$0 ;
        WHILE PTR#F% < EXT#F% BPUT#F%,0 : ENDWHILE
      ENDIF
      CLOSE #F%
      F% = FALSE
      ENDPROC
      
      DEF PROCerror(code%, message$)
      IF code% <> 100 message$ = "Internal error "+STR$code%
      PROCmessagebox("Line "+STR$ERL, message$, SDL_MESSAGEBOX_ERROR)
      ENDPROC
      
      DEF PROCmessagebox(title$, message$, flags%)
      LOCAL R%
      R% = FNmessagebox(title$, message$, flags%)
      ENDPROC
      
      DEF FNmessagebox(title$, message$, flags%)
      ON TIME LOCAL OFF
      ON MOUSE LOCAL OFF
      IF POS REM SDL thread sync
      LOCAL F%, H%, I%, L%, M%, N%, R%, S%, W%, X%, Y% : F% = @flags%
      LOCAL @char.x%, @char.y%, pal{}, svdu{} : DIM pal{0%(15)}, svdu{} = @vdu{} : svdu{} = @vdu{}
      IF BB4W% SYS "GetPaletteEntries", @hpal%, 0, 16, pal{} ELSE SYS "SDL_memcpy", pal{}, @hpal%, 64
      IF NOT BB4W% IF @vdu.hr% THEN LOCAL rc{} : DIM rc{0%(3)} : SYS "SDL_memcpy", rc{}, @vdu.hr%, 16
      @vdu.hf% = 0 : @vdu.hr% = 0 : OFF : *ESC OFF
      OSCLI "FONT " + GUIFont$
      PROC_setdialogpalette(Darkmode%)
      PRIVATE D% : IF D% = 0 THEN
        D% = FN_newdialog("", 160, 40)
        PROC_static(D%, "",     101, 4,  8, 40, 11, 0)
        PROC_button(D%, "OK",     1, 0, 22, 40, 11, 0)
        PROC_button(D%, "Abort",  3, 0, 22, 40, 11, 0)
        PROC_button(D%, "Retry",  4, 0, 22, 40, 11, 0)
        PROC_button(D%, "Ignore", 5, 0, 22, 40, 11, 0)
        PROC_button(D%, "Yes",    6, 0, 22, 40, 11, 0)
        PROC_button(D%, "No",     7, 0, 22, 40, 11, 0)
        PROC_button(D%, "Cancel", 2, 0, 22, 40, 11, 0) : REM Must be last (focus)
        PROC_button(D%, "Hidden", 8, 0, 22, 40, 11, &10000000)
      ENDIF
      REPEAT I% = INSTR(message$, CHR$&D+CHR$&A, R%)
        IF I% L% = WIDTH(MID$(message$, R%, I%-R%)) ELSE L% = WIDTH(MID$(message$, R%))
        IF I% N% += 2 * @char.y%
        R% = I% + 2 : IF L% > M% M% = L%
      UNTIL I% = 0
      PROC_getdlgrect(D%, L%, Y%, W%, H%)
      PROC_getdlgitemrect(D%, 8, X%, Y%, W%, H%)
      CASE flags% AND &F OF
        WHEN 1: R% = 2 : S% = %11000000000 : REM MB_OKCANCEL
        WHEN 2: R% = 3 : S% = %00000111000 : REM MB_ABORTRETRYIGNORE
        WHEN 3: R% = 3 : S% = %10011000000 : REM MB_YESNOCANCEL
        WHEN 4: R% = 2 : S% = %00011000000 : REM MB_YESNO
        WHEN 5: R% = 2 : S% = %10000010000 : REM MB_RETRYCANCEL
        OTHERWISE: R% = 1 : S% = %01000000000 : REM Just OK
      ENDCASE
      R% = R% * (W% + 20) + 20 : X% = L% + 20
      IF R% < M% + 50 X% += (M% + 50 - R%) DIV 2 : R% = M% + 50
      FOR I% = 3 TO 10
        IF S% AND (1 << I%) THEN
          PROC_showdlgitem(D%, I% AND 7, TRUE)
          PROC_setdlgitemrect(D%, I% AND 7, X%, Y% - N%, W%, H%)
          X% += W% + 20
        ELSE
          PROC_showdlgitem(D%, I% AND 7, FALSE)
        ENDIF
      NEXT
      PROC_getdlgitemrect(D%, 101, X%, Y%, W%, W%)
      PROC_setdlgitemrect(D%, 101, L% + (R% - M%) DIV 2, Y%, M% + 10, H% + N%)
      PROC_getdlgrect(D%, X%, Y%, W%, W%)
      PROC_setdlgrect(D%, L%, Y%, R%, 3.5 * H% + N%)
      PROC_setdlgitemtext(D%, 101, message$)
      PROC_setdialogtitle(D%, title$)
      PROC_registerdlgcallback(D%, FNdlgcb())
      R% = FN_showdialogex(D%, &FFFFFFFF80000000, &FFFFFFFF80000000, Darkmode%)
      PROC_closedialog(D%)
      VDU 26 : *FONT
      IF BB4W% IF @vdu.hr% SYS "DeleteObject", @vdu.hr%
      @vdu{} = svdu{}
      IF NOT BB4W% IF @vdu.hr% SYS "SDL_memcpy", @vdu.hr%, rc{}, 16
      IF BB4W% IF @vdu.hf% SYS "SelectObject", @memhdc%, @vdu.hf%
      IF BB4W% SYS "SetPaletteEntries", @hpal%, 0, 16, pal{} ELSE SYS "SDL_memcpy", @hpal%, pal{}, 64
      IF BB4W% SYS "SendMessage", @hwnd%, &402, 0, 0 : REM Update caret shape
      IF F% AND &40000000 ELSE *ESC ON
      = R%
      
      DEF PROCcleanup
      LOCAL R%,C%
      ON ERROR LOCAL IF FALSE THEN
        IF TBpressed&(16) PROCdebugcmd(0, &10000000)
      ENDIF : RESTORE ERROR
      FOR R% = 0 TO 5
        FOR C% = 0 TO 7
          ON ERROR LOCAL IF FALSE THEN
            OSCLI "DEL """ + @tmp$ + "cc" + Session$ + STR$R% + STR$C% + ".tmp.bmp"""
          ENDIF : RESTORE ERROR
        NEXT
      NEXT R%
      ON ERROR LOCAL IF FALSE THEN
        OSCLI "DEL """ + @tmp$ + "bbc" + Session$ + ".tmp.bmp"""
      ENDIF : RESTORE ERROR
      ON ERROR LOCAL IF FALSE THEN
        PROCundoclear(UndoLevel%, RedoLevel%)
      ENDIF : RESTORE ERROR
      ENDPROC
      
      REM!Crunch spaces,lines,rems
      REM!Resource @dir$+"sdlide.res"
      REM!Embed @lib$+"../bbcwrun6.exe",     @lib$+"../bbcwin6.exe",      @lib$+"../aplib.dll"
      REM!Embed @lib$+"../lib/treeview.bbc", @lib$+"../lib/filedlg.bbc",  @lib$+"../lib/dlglib.bbc"
      REM!Embed @lib$+"../lib/sdldebug.bbc", @lib$+"../lib/memusage.bbc", @lib$+"../lib/msgbox.bbc"
      REM!Embed @lib$+"../lib/menulib.bbc",  @lib$+"../lib/editbox.bbc",  @lib$+"../lib/winconsts.db"
      REM!Embed @lib$+"../examples/keywords.txt"
      
      REM!Embed @lib$+"../lib/ARRAYLIB.BBC", @lib$+"../lib/ASMLIB.BBC",   @lib$+"../lib/ASMLIB2.BBC"
      REM!Embed @lib$+"../lib/ASMLIBC.BBC",  @lib$+"../lib/BOX2DDBG.BBC", @lib$+"../lib/BOX2DGFX.BBC"
      REM!Embed @lib$+"../lib/BOX2DLIB.BBC", @lib$+"../lib/CALLBACK.BBC", @lib$+"../lib/CLASSLIB.BBC"
      REM!Embed @lib$+"../lib/COMLIB.BBC",   @lib$+"../lib/COMLIBA.BBC",  @lib$+"../lib/D3D9LIB.BBC"
      REM!Embed @lib$+"../lib/D3D9LIBA.BBC", @lib$+"../lib/D3DLIB.BBC",   @lib$+"../lib/D3DLIBA.BBC"
      REM!Embed @lib$+"../lib/DATELIB.BBC",  @lib$+"../lib/ELLIPSE.BBC",  @lib$+"../lib/EVENTLIB.BBC"
      REM!Embed @lib$+"../lib/FNUSING.BBC",  @lib$+"../lib/GDIPLIB.BBC",  @lib$+"../lib/HQSOUND.BBC"
      REM!Embed @lib$+"../lib/IMGLIB.BBC",   @lib$+"../lib/MDILIB.BBC",   @lib$+"../lib/MODE7LIB.BBC"
      REM!Embed @lib$+"../lib/MULTIWIN.BBC", @lib$+"../lib/NOWAIT.BBC",   @lib$+"../lib/ODBCLIB.BBC"
      REM!Embed @lib$+"../lib/SHADERLIB.BBC",@lib$+"../lib/SOCKLIB.BBC",  @lib$+"../lib/SORTLIB.BBC"
      REM!Embed @lib$+"../lib/SORTSALIB.BBC",@lib$+"../lib/SPRITELIB.BBC",@lib$+"../lib/STRINGLIB.BBC"
      REM!Embed @lib$+"../lib/SUBCLASS.BBC", @lib$+"../lib/SUBCLASSW.BBC",@lib$+"../lib/TIMERLIB.BBC"
      REM!Embed @lib$+"../lib/UTF8LIB.BBC",  @lib$+"../lib/WINLIB.BBC",   @lib$+"../lib/WINLIB2.BBC"
      REM!Embed @lib$+"../lib/WINLIB2A.BBC", @lib$+"../lib/WINLIB2B.BBC", @lib$+"../lib/WINLIB2U.BBC"
      REM!Embed @lib$+"../lib/WINLIB3.BBC",  @lib$+"../lib/WINLIB4.BBC",  @lib$+"../lib/WINLIB4U.BBC"
      REM!Embed @lib$+"../lib/WINLIB5.BBC",  @lib$+"../lib/WINLIB5A.BBC", @lib$+"../lib/WINLIB5U.BBC"
      REM!Embed @lib$+"../lib/WINLIB5W.BBC", @lib$+"../lib/WINLIBU.BBC",  @lib$+"../lib/XMLLIB.BBC"
      REM!Embed @lib$+"../lib/BOX2D221.DLL", @lib$+"../lib/D3DX8BBC.DLL", @lib$+"../lib/BBCMODE7.FNT"
      REM!Embed @lib$+"../lib/AAGFXLIB.BBC", @lib$+"../lib/SCRIPT.BBC",   @lib$+"../lib/WEBGLLIB.BBC"