Re: my variables in a subroutine

Further to ikegami's post, in case you are not using 5.10 yet, the following 'hack' works as well:

use strict;
use warnings; 

{   # Outer block

    my $keeps_value = 0;

    sub mysub {
        print "$keeps_value\n";
        $keeps_value++
    }

}   # End of outer block

mysub();
mysub();
mysub();
[download]

Produces:

0
1
2
[download]

The varibale $keeps_value is not visible outside the block.

Comment on Re: my variables in a subroutine Select or Download Code

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Re^2: my variables in a subroutine by Bloodnok (Vicar) on Mar 23, 2009 at 11:51 UTC
Your example isn't a hack as such, it is, as lakshmananindia pointed out, a closure. A user level that continues to overstate my experience :-))	[reply]
Re^3: my variables in a subroutine by cdarke (Prior) on Mar 23, 2009 at 11:59 UTC
Semantics, one man's hack is another's feature. I view it as a hack because it fulfills functionality missing from the language, i.e. a 'state' variable type (aka 'static') (and if it wasn't a missing feature then it wouldn't have been added).	[reply]
Re^4: my variables in a subroutine by Anomynous Monk (Scribe) on Mar 23, 2009 at 16:38 UTC
That's not a hack, it's a Design Pattern!	[reply]