#!/usr/bin/perl --

use strict;
# use warnings;

sub factoryOne {
    my ($var) = (@_);
    print "factory: '$var'\n";
    return sub {
        eval { print "eval:    '$var'\n" };
    }
}

sub factoryTwo {
    my ($var) = (@_);
    print "factory: '$var'\n";
    return sub {
        my $estr = "print \"eval:    '\$var'\n\"";
        eval $estr;
    }
}

sub factoryThree {
    my ($var) = (@_);
    print "factory: '$var'\n";
    return sub {
        $var;
        my $estr = "print \"eval:    '\$var'\n\"";
        eval $estr;
    }
}

my $f = factoryOne('lulz');
$f->();

my $g = factoryTwo('frunz');
$g->();

my $h = factoryThree('lulz');
$h->();

[download]
yields: 
factory: 'lulz'
eval:    'lulz'
factory: 'frunz'
eval:    ''
factory: 'lulz'
eval:    'lulz'

[download]

the first factory works as expected, the second two don't, really.

two questions:
1) why isn't $var in scope inside the eval inside the closure inside factoryTwo?
2) why does referencing $var in the closure remedy 1) in factoryThree?

In reply to i don't understand this scope behavior w/ closures and eval by xandercrews

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