Re: assign to magic name-of-function variable instead of "return"

[abigail]

On Mon, Feb 05, 2001 at 12:29:34PM -0500, John Porter wrote:
> James Mastros wrote:
> > OTOH, for functions that look more like {startup;
> > compute; teardown}, magic-varable is nice.  Think of the functions where you
> > have a varable named $ret or somesuch, and you compute it, have another few
> > lines or few screens of code, and then say "return $ret".  
> 
> I see this all the time.  What would fit the bill is to have something
> like a C<continue> block for subs; they get called during the same
> phase as destructors of objects going out of scope.
> 
>     sub readit {
>         open F, "< $f" or die "$f: $!"; # even in the tiniest example
>         my $l = <F>;
>         close F;
>         $l
>     }
> 
> becomes
> 
>     sub readit {
>         open F, "< $f" ...
>         scalar(<F>)
>     }
>     continue {
>         close F;
>     }
> 
> O.k., the example is a little bogus, what with IO::File etc.
> But for the general case...

We can do something like this already in perl5. There's even a module 
on CPAN for it: "End".

    use End;

    {   my $foo = end {print "Leaving the block\n"};
        ...
        last;     # Prints "Leaving the block\n".
        ...
    }



Abigail