&get_and_inc_foo is a closure, because it binds a lexical variable defined outside of it.

If my example is a closure, then aren't all subroutines closures over the file-scoped lexicals in the file they're defined in?

If they don't use any lexicals defined outside them, they're not closures. sub foo { 1 } isn't a closure no matter where it's defined. 

    my $foo;

    sub closure { $foo }
    sub not_closure { 1 }

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What I mean with making the subroutine a lexical anonymous subroutine is the following. 
    my $foo;                 # lexical
    $foo = sub { $foo->() }; # closure

    local $bar;              # dynamical
    $bar = sub { $bar->() }; # not a closure

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ihb

Read argumentation in its context!

In reply to Re^6: Is it possible to create a sub exclusive to a sub? (nasty memory leak) by ihb
in thread Is it possible to create a sub exclusive to a sub? by punkish

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