But, but, the docs imply that this is the syntax for a function that returns an array of bytes.

fpc ios7crypt.pas
ios7crypt.pas(3,25) Error: Type identifier expected
ios7crypt.pas(3,25) Fatal: Syntax error, ";" expected but "ARRAY" found
Fatal: Compilation aborted
$ cat ios7crypt.pas
program IOS7Crypt;

function XlatPrime () : array of byte;
begin
XlatPrime := (
$64, $73, $66, $64, $3b, $6b, $66, $6f,
$41, $2c, $2e, $69, $79, $65, $77, $72,
$6b, $6c, $64, $4a, $4b, $44, $48, $53,
$55, $42, $73, $67, $76, $63, $61, $36,
$39, $38, $33, $34, $6e, $63, $78, $76,
$39, $38, $37, $33, $32, $35, $34, $6b,
$3b, $66, $67, $38, $37
);
end;

function Encrypt (hash : string) : string;
begin
Encrypt := 'abc';
end;
function Decrypt (hash : string) : string;
begin
Decrypt := 'abc';
end;
var
password : string;
hash : string;
begin
password := 'abc';
hash := Encrypt(password);
password := Decrypt(hash);
write('Password: ');
 writeln(password);
end.

Cheers,

Andrew Pennebaker
www.yellosoft.us

2011/10/18 Andrew Pennebaker :

But, but, the docs imply that this is the syntax for a function that returns an array of bytes.

Where in the docs did you read this?

Vincent

Andrew Pennebaker wrote

function XlatPrime () : array of byte; begin XlatPrime := ( $64, $73, $66, $64, $3b, $6b, $66, $6f,

I think that a syntax similar to this is available only for constant initialization. Actually I remember it from constant initialization for records. Maybe it works for arrays too.

The usual way to set a dynamic array is:

function XlatPrime () : array of byte;
begin
  SetLength(XlatPrime, 20);
  XlatPrime[0] := $64;
  XlatPrime[1] := $73;
  etc

But you can also try this (maybe it works):

function XlatPrime () : array of byte;
const ConstXlatPrime: array[0..19] of Byte = (
 $64, $73, $66, $64, $3b, $6b, $66, $6f,....);
begin
  Result := ConstXlatPrime;
end;

Andrew Pennebaker wrote

But, but, the docs imply that this is the syntax for a function that returns an array of bytes.

[snip]

Free Pascal (and Delphi and TP) does not support such syntax. I suggest you that you define your array as a const instead of a function and just use that.

E.g.

const
XlatPrime: array[0..52] of Byte = (
$64, $73, $66, $64, $3b, $6b, $66, $6f,
$41, $2c, $2e, $69, $79, $65, $77, $72,
$6b, $6c, $64, $4a, $4b, $44, $48, $53,
$55, $42, $73, $67, $76, $63, $61, $36,
$39, $38, $33, $34, $6e, $63, $78, $76,
$39, $38, $37, $33, $32, $35, $34, $6b,
$3b, $66, $67, $38, $37

   );

It is necessary to specify the element count correctly.

Note: In trunk you should be able to do the following:

type
   TByteArray = array of Byte;

function XlatPrime(): TByteArray;
begin

   XlatPrime := TByteArray.Create(
     $64, $73, $66, $64, $3b, $6b, $66, $6f,
     $41, $2c, $2e, $69, $79, $65, $77, $72,
     $6b, $6c, $64, $4a, $4b, $44, $48, $53,
     $55, $42, $73, $67, $76, $63, $61, $36,
     $39, $38, $33, $34, $6e, $63, $78, $76,
     $39, $38, $37, $33, $32, $35, $34, $6b,
     $3b, $66, $67, $38, $37
   );

end;

This feature was introduced because of Delphi compatibilty (and I still have the opinion that it would be nice if that would be extended for "unnamed" array types as well...)

Regards,
Sven

Before I forget it: If you use this solution (not the const one) or you use "SetLength", you need to free the array using "SetLength(0)" or "YourArrayVariable := Nil", otherwise you'll have a memory leak. You must not do this if you use the const solution.

Regards,
Sven

2011/10/18 Sven Barth :

That is unexpected. Until now, SetLength was used for ansistrings and dynamic arrays, which didn't have this requirement (unless you messed with the internals using Move).

Vincent

Could be that I missed the reference counting of arrays. At least I always try to "free" my arrays by hand ^^

Regards,
Sven

Yes, seems like I missed the ref counting. See
http://www.freepascal.org/docs-html/ref/refsu15.html#x39-430003.3.1

====
As remarked earlier, dynamic arrays are reference counted: if in one of the previous examples A goes out of scope and B does not, then the array is not yet disposed of: the reference count of A (and B) is decreased with 1. As soon as the reference count reaches zero the memory, allocated for the contents of the array, is disposed of. ====

Regards,
Sven

RRUZ<http://stackoverflow.com/questions/7802319/whats-the-syntax-for-literal-arrays-in-free-pascal>has the answer:

const
XLAT_SIZE = 53;
xlat : Array[0..XLAT_SIZE-1] of Integer = (
$64, $73, $66, $64, $3b, $6b, $66, $6f,
$41, $2c, $2e, $69, $79, $65, $77, $72,
$6b, $6c, $64, $4a, $4b, $44, $48, $53,
$55, $42, $73, $67, $76, $63, $61, $36,
$39, $38, $33, $34, $6e, $63, $78, $76,
$39, $38, $37, $33, $32, $35, $34, $6b,
$3b, $66, $67, $38, $37
);

Works for me!

Cheers,

Andrew Pennebaker
www.yellosoft.us