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Programming => Networking and Web Programming => Pas2JS => Topic started by: Kryvich on January 22, 2019, 12:22:40 pm

Title: Pas2js, typed arrays and ANSI strings
Post by: Kryvich on January 22, 2019, 12:22:40 pm

Hi,
Can Pas2js transpile Delphi/FPC typed arrays to their counterparts in JavaScript (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray)? I mean

• array of Integer -> Int32Array
• array of Byte -> UInt8Array
• array of Word -> UInt16Array
• etc.

I see declarations of TJSInt32Array, TJSUint8Array, TJSUint16Array in js.pas, but when I try to transpile my test program I can't find these names in the result JS file.

If/when these arrays will be supported by the transpiler, we can move further and try to convert AnsiStrings as UInt8Array.

Title: Re: Pas2js, typed arrays and ANSI strings
Post by: Kryvich on January 22, 2019, 01:23:02 pm

OK I can use JavaScript typed arrays using bindings from js.pas!

Code: Pascal  [Select][+][-]

1. program TestTypedArrays;
2. {$IFDEF PAS2JS}
3. uses
4.   JS;
5. {$ENDIF}
6.  
7. type
8. {$IFDEF PAS2JS}
9.   TByteArray = TJSUint8Array;
10.   TWordArray = TJSUint16Array;
11. {$ELSE}
12.   TByteArray = array of Byte;
13.   TWordArray = array of Word;
14. {$ENDIF}
15.  
16. procedure Test;
17. var
18.   ba: TByteArray;
19.   wa: TWordArray;
20. begin
21. {$IFDEF PAS2JS}
22.   ba := TByteArray.new(10);
23. {$ELSE}
24.   SetLength(ba, 10);
25. {$ENDIF}
26.   ba[0] := $FF;
27. {$IFDEF PAS2JS}
28.   wa := TWordArray.new(20);
29. {$ELSE}
30.   SetLength(wa, 20);
31. {$ENDIF}
32.   wa[1] := $FFEE;
33.   Writeln('ba[0] = ', ba[0], ', wa[1] = ', wa[1]);
34. end;
35.  
36. begin
37.   Test;
38. end.

But there is too much IFDEFs. Would be nice to have the same syntax as in Delphi/FPC.

Title: Re: Pas2js, typed arrays and ANSI strings
Post by: mattias on February 18, 2019, 06:20:16 pm

At the moment all dynamic arrays are TJSArrays.
Using the typed arrays is an interesting proposal.