Depends where you declare it.

my $keeps_value;

sub func {
   my $loses_value;
   state $also_keeps_value;   # Perl 5.10
   ...
}
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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();
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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 :-))

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).

Refer How to post a question

I think you need closures. If not, please explain your question?

Read closures in Advanced Programming in perl by Sriram srinivasan