Don't do that. As you mentioned, my @a unless @n; is officially undefined behaviour. Instead, use 

{
    my @a;

    sub load {
        push @a, @n;
        @a
    }
}

[download]
or 
use feature qw( state );

sub load {
    state $a = [];
    push @$a, @n;
    @$a
}

[download]

In reply to Re^2: Surely @a is local to sub load? by ikegami
in thread Surely @a is local to sub load? by philiprbrenan

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