This seems to be what use feature 'state' is made for. 
#!/usr/bin/env perl


# demo of closure around sub, with persistent string

use strict;
use warnings;
use feature 'state';

for my $q ('a'..'g') {
    do_something($q);
    print "Done computing\n"
}


sub do_something {
    state $FIXED_STRING = 'fixed_string';
    state %persistent;
    my $x = $_[0];

    $persistent{$x}{$FIXED_STRING} = rand;

    END {
        for my $k (keys %persistent) {
            print "$k: $persistent{$k}{$FIXED_STRING}\n";
        }
    }
}

[download]
Bill

In reply to Re: Closure Over Scalar? by BillKSmith
in thread Closure Over Scalar? by QM

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