> On May 25, 2023, at 1:10 PM, Michael Van Canneyt via fpc-pascal
> <fpc-pascal@lists.freepascal.org> wrote:
>
>
> In C you need to do something like this:
>
> Function MyFunction(out theresult : TResultType) : Integer;
>
> begin
> Allocate A
> ...
> error condition 1:
> Free A, exit (1);
> ...
> Allocate B
> error condition 2:
> Free A, Free B, exit(2)
>
> Allocate C
> error condition 3:
> Free A, Free B, free C, exit(3);
> ...
> // etc
> // All went well, report 0
> theresult:=X;
> Free A, Free B, free C exit(0);
> end.
Indeed this is an ideal example of why they were invented and it makes sense
here. Honestly most of this mess could be cleaned up with smart pointers also
and not upset control flow like exceptions do.
I'm doing work with Swift right now and in particular a web framework that
makes lots of database calls, all of which can fail so we use exceptions
everywhere. The thing that Swift does well and FPC does not, is that it labels
the functions as "throws" and calls have a "try" keyword before them so you
know how the control flow is actually working.
Because FPC doesn't do this any function could throw errors and thus those
stack frames are inserted everywhere and add needless overhead when exceptions
aren't used. It's also nice to not have hidden control flow potential on any
function call
Regards,
Ryan Joseph
_______________________________________________
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
