xgraph.pas "failure 235/35 can't read Variables of this type"

[coradi]

It's from the Book, Turbo Pascal for Kids

xgraph.pas

Got the failure  235/35 can't read Variables of this type

Code: [Select]

{-----------------------------------------------------------------------
This unit declares a unit containing procedures etc. that are normally
(i.e., in Turbo Pascal) provided by the units 'graph' and 'crt'. The actual
implementation of most of these is not contained in this unit, but in
puff_c.c, which is written in C, and uses the X11 window system (hence
this unit's name).
The implementations here and in puff_c.c are not complete: they are limited
to what is needed for compiling and using the PUFF software. As such, they
may or may not be useful for compiling other graphical Turbo Pascal
applications under Linux, depending on the requirements of such applications.
This unit and puff_c.c also contain a few other routines that were used in
the Linux port of PUFF but do not exist in Turbo Pascal: these were needed
because some things must (for efficiency or other reasons) be implemented
differently on Linux than on MS-DOS.
Parts (support for readln and writeln) are copyright (c) 1999-2000 by Michael
Van Canneyt and Peter Vreman, members of the Free Pascal development team.
Rest is copyright (c) 2000, by Pieter-Tjerk de Boer, pa3fwm@amsat.org.
This software is distributed under the conditions of version 3 of the GNU
General Public License from the Free Software Foundation.
-----------------------------------------------------------------------}

{$T-}    {No output sections}

Unit xgraph;


Interface


TYPE
  ViewPortType = Record
    X1,Y1,X2,Y2 : Integer;
    Clip : Boolean
  end;


Procedure InitGraph (var GraphDriver,GraphModus : integer; const PathToDriver : string); cdecl; external;
Procedure CloseGraph ; cdecl; external;

Procedure SetColor (Color : Longint); cdecl; external;
Procedure SetFillStyle (Pattern,Color : Longint); cdecl; external;
Procedure SetLineStyle (LineStyle,Pattern,Width : Longint); cdecl; external;

Procedure Line (X1,Y1,X2,Y2 : Longint); cdecl; external;
Procedure PutPixel (X,Y : Longint; Color : Longint); cdecl; external;
Procedure Bar (X1,Y1,X2,Y2 : Longint); cdecl; external;
Procedure Rectangle (X1,Y1,X2,Y2 : Longint); cdecl; external;
Procedure Arc (X,Y : Longint; start,stop, radius : Longint); cdecl; external;
Procedure FillEllipse (X,Y : Longint; Xradius,YRadius: Longint); cdecl; external;
Procedure Circle (X,Y : Longint; Radius : Longint); cdecl; external;
Procedure FloodFill (X,Y : Longint; BorderColor : Longint); cdecl; external;

Procedure SetTextJustify (Horizontal,Vertical : Longint); cdecl; external;
Procedure OutTextXY (X,Y : Integer; Const TextString : String);

Procedure SetViewPort (X1,Y1,X2,Y2 : Longint; Clip : Boolean); cdecl; external;

Function GetBkColor : Longint; cdecl; external;
Procedure SetBkColor (Color : Longint); cdecl; external;

Function GraphErrorMsg (ErrorCode : Longint) : String; cdecl; external;
Function GraphResult : Longint; cdecl; external;


Procedure GetBox(bn, x, y, width, height: Longint); cdecl; external;
Procedure PutBox(bn, x, y, width, height: Longint); cdecl; external;


VAR
  ScreenHeight:integer; external name 'ScreenHeight';
  ScreenWidth:integer; external name 'ScreenWidth';


CONST
  SOLIDFILL=0;
  lefttext=0;
  centertext=1;
  righttext=2;
  userbitln=4;
  normwidth=1;
  solidln=0;
  VGA=0;
  EGA=1;
  GROK=0;





CONST
  Black = 0;
  Blue = 1;
  Green = 2;
  Cyan = 3;
  Red = 4;
  Magenta = 5;
  Brown = 6;
  LightGray = 7;
  DarkGray = 8;
  LightBlue = 9;
  LightGreen = 10;
  LightCyan = 11;
  LightRed = 12;
  LightMagenta = 13;
  Yellow = 14;
  White = 15;
  co80 = 3;
  WindMax: Word = $184f;
  LastMode: Word = 3;
  DirectVideo: Boolean = False;




Procedure Window (X1, Y1, X2, Y2: Longint); cdecl; external name 'crtWindow';
Procedure GotoXY (X: Longint; Y: Longint); cdecl; external;
Procedure Sound (hz : Longint); cdecl; external;
Procedure Delay (DTime: Longint); cdecl; external;
Procedure NoSound ; cdecl; external;
Function KeyPressed : Boolean; cdecl; external;
Function ReadKey : Char; cdecl; external;
procedure TextMode(Mode: Longint); cdecl; external;
Procedure TextColor (CL: Longint); cdecl; external;
Procedure TextBackground (CL: Longint); cdecl; external;
Procedure ClrScr ; cdecl; external;


Function GetTimerTicks : Integer; cdecl; external;




Implementation


uses dos,linux;




Procedure C_OutTextXY (X,Y : Longint; Var TextString : String); cdecl; external;

Procedure OutTextXY (X,Y : Integer; Const TextString : String);
var s: string;
begin
   s:=TextString;
   C_OutTextXY(X,Y,s);
end;




{ write(ln) and readln support code based on rtl/linux/crt.pp from the fpc source tree }

procedure DoWrite(var s: string); cdecl; external;
procedure DoWriteEnd; cdecl; external;


Function xgraphWrite(Var F: TextRec): Integer;
Var
  Temp : String;
  idx,i : Longint;
Begin
  idx:=0;
  while (F.BufPos>0) do
   begin
     i:=F.BufPos;
     if i>255 then
      i:=255;
     Move(F.BufPTR^[idx],Temp[1],i);
     SetLength(Temp,i);
     DoWrite(Temp);
     dec(F.BufPos,i);
     inc(idx,i);
   end;

  DoWriteEnd;
  xgraphWrite:=0;
End;



Function xgraphRead(Var F: TextRec): Integer;
{
  Read from CRT associated file.
}
var
  c : char;
  i : longint;
Begin
      F.BufPos := 0;
      i := 0;
      repeat
        c := readkey;
        case c of
          { ignore special keys }
          #0:
            c:= readkey;
          { Backspace }
          #8:
            if i > 0 then
              begin
                write(#8#32#8);
                dec(i);
              end;
          { Unhandled extended key }
          #27:;
          { CR }
          #13:
            begin
              F.BufPtr^[i] := #10;
              write(#10);
              inc(i);
            end;
          else
            begin
              write(c);
              F.BufPtr^[i] := c;
              inc(i);
            end;
        end;
      until (c in [#10,#13]) or (i >= F.BufSize);
      F.BufEnd := i;
      xgraphRead := 0;
      exit;
End;


Function xgraphReturn(Var F:TextRec):Integer;
Begin
  xgraphReturn:=0;
end;




Function xgraphOpen(Var F: TextRec): Integer;
Begin
  If F.Mode=fmOutput Then
   begin
     TextRec(F).InOutFunc:=@xgraphWrite;
     TextRec(F).FlushFunc:=@xgraphWrite;
   end;
  If F.Mode=fmInput Then
   begin
     TextRec(F).InOutFunc:=@xgraphRead;
     TextRec(F).FlushFunc:=@xgraphReturn;
   end;
  xgraphOpen:=0;
End;



procedure init_x; cdecl; external;


Initialization

  Assign(Output,'');
  TextRec(Output).OpenFunc:=@xgraphOpen;
  Rewrite(Output);
  TextRec(Output).Handle:=StdOutputHandle;
  Assign(Input,'');
  TextRec(Input).OpenFunc:=@xgraphOpen;
  Reset(Input);
  TextRec(Input).Handle:=StdInputHandle;

  init_x();
{
  ScreenHeight:=500;
  ScreenWidth:=1000;
}

end.


[Thaddy]

Turbo Pascal did not support initialization sections. It also did not support for in do and some more places where you mixed up the syntax with modern Pascal. You screwed up, I am afraid. Modes are important for features to be supported.
Also note that to test such code you should use {$mode tp}

btw: I got a completely unrelated error while compiling your code in mode tp -: unexpected end of file.

[Bart]

Are you using this unit with TP or with fpc?
I don't get compilation errors with fpc (well it won't link, since I don't have the external libraries it needs).

Bart

[marcov]

Maybe he is in an IDE that forces some objfpc/delphi mode on the cmdline, and strings become ansistrings or so ?

[coradi]

I use it on Freepascal in DOS Mode, and copied the Units

It's Turbo pascal / from the BOOK Torbo PAscal and Delphi for kids.
Is copy paste from CD
https://www.amazon.de/Turbo-Pascal-Delphi-für-Kids/dp/3826606426/ref=sr_1_1?__mk_de_DE=ÅMÅŽÕÑ&crid=12Z7V8RCP57QE&keywords=turbo+pascal+kids&qid=1669214774&sprefix=turbo+pascal+kids%2Caps%2C215&sr=8-1

[Thaddy]

Code: Pascal  [Select][+][-]

1. {-----------------------------------------------------------------------
2. This unit declares a unit containing procedures etc. that are normally
3. (i.e., in Turbo Pascal) provided by the units 'graph' and 'crt'. The actual
4. implementation of most of these is not contained in this unit, but in
5. puff_c.c, which is written in C, and uses the X11 window system (hence
6. this unit's name).
7. The implementations here and in puff_c.c are not complete: they are limited
8. to what is needed for compiling and using the PUFF software. As such, they
9. may or may not be useful for compiling other graphical Turbo Pascal
10. applications under Linux, depending on the requirements of such applications.
11. This unit and puff_c.c also contain a few other routines that were used in
12. the Linux port of PUFF but do not exist in Turbo Pascal: these were needed
13. because some things must (for efficiency or other reasons) be implemented
14. differently on Linux than on MS-DOS.
15. Parts (support for readln and writeln) are copyright (c) 1999-2000 by Michael
16. Van Canneyt and Peter Vreman, members of the Free Pascal development team.
17. Rest is copyright (c) 2000, by Pieter-Tjerk de Boer, pa3fwm@amsat.org.
18. This software is distributed under the conditions of version 3 of the GNU
19. General Public License from the Free Software Foundation.
20. Editted version by Thaddy de Koning 2022. Should be cleaned up further because this is NOT the original version.
21. Some fool screwed it up and I just did damage control.
22. -----------------------------------------------------------------------}
23.  
24. {.$T-}    {No output sections} //bollocks
25. {$mode fpc}
26. Unit xgraph;
27. {.$mode tp} // this code is a mess and won't compile under its target TP mode. This is FPC mode
28.  
29. Interface
30.  
31.  
32. TYPE
33.   ViewPortType = Record
34.     X1,Y1,X2,Y2 : Integer;
35.     Clip : Boolean
36.   end;
37.  
38.  
39. Procedure InitGraph (var GraphDriver,GraphModus : integer; const PathToDriver : string); cdecl; external;
40. Procedure CloseGraph ; cdecl; external;
41.  
42. Procedure SetColor (Color : Longint); cdecl; external;
43. Procedure SetFillStyle (Pattern,Color : Longint); cdecl; external;
44. Procedure SetLineStyle (LineStyle,Pattern,Width : Longint); cdecl; external;
45.  
46. Procedure Line (X1,Y1,X2,Y2 : Longint); cdecl; external;
47. Procedure PutPixel (X,Y : Longint; Color : Longint); cdecl; external;
48. Procedure Bar (X1,Y1,X2,Y2 : Longint); cdecl; external;
49. Procedure Rectangle (X1,Y1,X2,Y2 : Longint); cdecl; external;
50. Procedure Arc (X,Y : Longint; start,stop, radius : Longint); cdecl; external;
51. Procedure FillEllipse (X,Y : Longint; Xradius,YRadius: Longint); cdecl; external;
52. Procedure Circle (X,Y : Longint; Radius : Longint); cdecl; external;
53. Procedure FloodFill (X,Y : Longint; BorderColor : Longint); cdecl; external;
54.  
55. Procedure SetTextJustify (Horizontal,Vertical : Longint); cdecl; external;
56. Procedure OutTextXY (X,Y : Integer; Const TextString : String);
57.  
58. Procedure SetViewPort (X1,Y1,X2,Y2 : Longint; Clip : Boolean); cdecl; external;
59.  
60. Function GetBkColor : Longint; cdecl; external;
61. Procedure SetBkColor (Color : Longint); cdecl; external;
62.  
63. Function GraphErrorMsg (ErrorCode : Longint) : String; cdecl; external;
64. Function GraphResult : Longint; cdecl; external;
65.  
66.  
67. Procedure GetBox(bn, x, y, width, height: Longint); cdecl; external;
68. Procedure PutBox(bn, x, y, width, height: Longint); cdecl; external;
69.  
70.  
71. VAR
72.   ScreenHeight:integer; external name 'ScreenHeight'; // unsuported by TP
73.   ScreenWidth:integer; external name 'ScreenWidth';   // unsupported by tp
74.  
75.  
76. CONST
77.   SOLIDFILL=0;
78.   lefttext=0;
79.   centertext=1;
80.   righttext=2;
81.   userbitln=4;
82.   normwidth=1;
83.   solidln=0;
84.   VGA=0;
85.   EGA=1;
86.   GROK=0;
87.  
88.  
89.  
90.  
91.  
92. CONST
93.   Black = 0;
94.   Blue = 1;
95.   Green = 2;
96.   Cyan = 3;
97.   Red = 4;
98.   Magenta = 5;
99.   Brown = 6;
100.   LightGray = 7;
101.   DarkGray = 8;
102.   LightBlue = 9;
103.   LightGreen = 10;
104.   LightCyan = 11;
105.   LightRed = 12;
106.   LightMagenta = 13;
107.   Yellow = 14;
108.   White = 15;
109.   co80 = 3;
110.   WindMax: Word = $184f;
111.   LastMode: Word = 3;
112.   DirectVideo: Boolean = False;
113.  
114.  
115.  
116.  
117. Procedure Window (X1, Y1, X2, Y2: Longint); cdecl; external name 'crtWindow';
118. Procedure GotoXY (X: Longint; Y: Longint); cdecl; external;
119. Procedure Sound (hz : Longint); cdecl; external;
120. Procedure Delay (DTime: Longint); cdecl; external;
121. Procedure NoSound ; cdecl; external;
122. Function KeyPressed : Boolean; cdecl; external;
123. Function ReadKey : Char; cdecl; external;
124. procedure TextMode(Mode: Longint); cdecl; external;
125. Procedure TextColor (CL: Longint); cdecl; external;
126. Procedure TextBackground (CL: Longint); cdecl; external;
127. Procedure ClrScr ; cdecl; external;
128.  
129.  
130. Function GetTimerTicks : Integer; cdecl; external;
131.  
132.  
133.  
134.  
135. Implementation
136.  
137.  
138. uses dos;
139.  
140.  
141.  
142.  
143. Procedure C_OutTextXY (X,Y : Longint; Var TextString : String); cdecl; external;
144.  
145. Procedure OutTextXY (X,Y : Integer; Const TextString : String);
146. var s: string;
147. begin
148.    s:=TextString;
149.    C_OutTextXY(X,Y,s);
150. end;
151.  
152.  
153.  
154.  
155. { write(ln) and readln support code based on rtl/linux/crt.pp from the fpc source tree }
156.  
157. procedure DoWrite(var s: string); cdecl; external;
158. procedure DoWriteEnd; cdecl; external;
159.  
160.  
161. Function xgraphWrite(Var F: TextRec): Integer;
162. Var
163.   Temp : String;
164.   idx,i : Longint;
165. Begin
166.   idx:=0;
167.   while (F.BufPos>0) do
168.    begin
169.      i:=F.BufPos;
170.      if i>255 then
171.       i:=255;
172.      Move(F.BufPTR^[idx],Temp[1],i);
173.      SetLength(Temp,i);
174.      DoWrite(Temp);
175.      dec(F.BufPos,i);
176.      inc(idx,i);
177.    end;
178.  
179.   DoWriteEnd;
180.   xgraphWrite:=0;
181. End;
182.  
183.  
184.  
185. Function xgraphRead(Var F: TextRec): Integer;
186. {
187.   Read from CRT associated file.
188. }
189. var
190.   c : char;
191.   i : longint;
192. Begin
193.       F.BufPos := 0;
194.       i := 0;
195.       repeat
196.         c := readkey;
197.         case c of
198.           { ignore special keys }
199.           #0:
200.             c:= readkey;
201.           { Backspace }
202.           #8:
203.             if i > 0 then
204.               begin
205.                 write(#8#32#8);
206.                 dec(i);
207.               end;
208.           { Unhandled extended key }
209.           #27:;
210.           { CR }
211.           #13:
212.             begin
213.               F.BufPtr^[i] := #10;
214.               write(#10);
215.               inc(i);
216.             end;
217.           else
218.             begin
219.               write(c);
220.               F.BufPtr^[i] := c;
221.               inc(i);
222.             end;
223.         end;
224.       until (c in [#10,#13]) or (i >= F.BufSize);
225.       F.BufEnd := i;
226.       xgraphRead := 0;
227.       exit;
228. End;
229.  
230.  
231. Function xgraphReturn(Var F:TextRec):Integer;
232. Begin
233.   xgraphReturn:=0;
234. end;
235.  
236.  
237.  
238.  
239. Function xgraphOpen(Var F: TextRec): Integer;
240. Begin
241.   If F.Mode=fmOutput Then
242.    begin
243.      TextRec(F).InOutFunc:=@xgraphWrite;
244.      TextRec(F).FlushFunc:=@xgraphWrite;
245.    end;
246.   If F.Mode=fmInput Then
247.    begin
248.      TextRec(F).InOutFunc:=@xgraphRead;
249.      TextRec(F).FlushFunc:=@xgraphReturn;
250.    end;
251.   xgraphOpen:=0;
252. End;
253.  
254.  
255.  
256. procedure init_x; cdecl; external;
257.  
258.  
259. Initialization
260.  
261.   Assign(Output,'');
262.   TextRec(Output).OpenFunc:=@xgraphOpen;
263.   Rewrite(Output);
264.   TextRec(Output).Handle:=StdOutputHandle;
265.   Assign(Input,'');
266.   TextRec(Input).OpenFunc:=@xgraphOpen;
267.   Reset(Input);
268.   TextRec(Input).Handle:=StdInputHandle;
269.  
270.   init_x();
271. {
272.   ScreenHeight:=500;
273.   ScreenWidth:=1000;
274. }
275.  
276. end.

Works. But it still is a gigantic mess and bad coding. And the bad coding is NOT!! from that book.....
Well, I  am a pensionado with little else to do, but please be honest if you mess up things yourself. (and help my 14 year old daughter with maths... which is worse than fixing this)

This is for mode fpc. I am not inclined to fix it for mode tp. I could have watched Japan beating Germany in the mean time - forever - 
Why did you not write you have made modifications? That is wrong, very wrong. Especially if these mods are very wrong.

[Bart]

Can't you just use graph or ptgraph unit that come with fpc?

Bart

[Thaddy]

He could have.

[coradi]

yes, it in on the CD from the book...I mean

That's the complete Program

[Thaddy]

Liar.
There is no for in do in TP, nor initialization sections.
I am not prepared to help you any further.
 YOU messed up.
Either it is a wrong book or you are wrong.

(note that I myself have made bold and wrong statements too (dismissed by mainly Sarah) but never lied.)

As I suspect that the author of this "book" is a forum member I would suggest he/she would answer.
But if you changed the code you should apologize. Wasting time only pensionado's can afford...barely!
(My first band was 51 years ago, my best band is 40 years ago: resp. Tombstone and The Duvel. I do not imagine to beat that time span)