> Vinzent H?fler> Probably you should used a "packed record", though. And it's
> in no
> Vinzent H?fler> way portable, of course.
> Also correct.
> Jonas
I use
{$A-}
abc= record
something: byte;
case byte of
1: (a,b: byte);
2: (c: word);
end;
{$A+} // or even a: byte; rsrvd1: array[1..3] of byte; b: word; ...
{$IF sizeof(abc)<>1234}
{$FATAL Неверный размер записи для заголовка (sizeof(abc)<>1234).} // I think,
there is no need to translate:)
{$ENDIF}
because I read binaries generated by other programs. So it's mostly portable:
if it was supposed to be really portable, I'd add endianness checking.
What am I thinking of is a construction like
xyz= object
raw: abc;
function GetA: byte;
function GetB: byte;
function GetC: word;
property something: byte READ raw.something;
property a: byte READ GetA;
property b: byte READ GetB;
property c: word READ GetC;
procedure GetData(...); // obtain data for the first time, writes to the
'raw'
end;
function xyz.GetA: byte;
begin if something=1 then GetA:= raw.a else
Show_Fatal_Error_Message(Fatal_Error_ID); end;
function xyz.GetB: byte;
begin if something=1 then GetB:= raw.b else
Show_Fatal_Error_Message(Fatal_Error_ID); end;
function xyz.GetC: word;
begin if something=2 then GetC:= raw.c else
Show_Fatal_Error_Message(Fatal_Error_ID); end;
But it's somewhat bulky (in the case of many types), so I hoped there is a
language feature for my convenience (I don't know pascal very well and didn't
understand corresponding documentation in the one way).
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