This is an example of a closure:

my $apr;

sub handler {
    my $r = shift;
    $apr = Apache::Request->new($r);
    other_sub();
}

sub other_sub {
    my $foo = $apr->some_method();
}

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Basically, anything where a sub refers to a lexical defined outside of the sub.

In reply to Re^3: Calls to Apache::Request's param method sometimes end the program and return no data by perrin
in thread Calls to Apache::Request's param method sometimes end the program and return no data by cfreak

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