Actually, it doesn't need to be anonymous or a code ref to be a closure; it just has to refer to lexical variables defined outside of its scope. This is a closure: 
my $foo;
sub bar {
    print $foo;
}

[download]
Any further changes to the value of $foo in the future will not change the private value that bar() now has.

In reply to Re: (Ovid) Re: Sub Definitions Within Subs: Best Way to Exploit by perrin
in thread Sub Definitions Within Subs: Best Way to Exploit by crazysniffable

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