Hello shawnhcorey,

This is nice, but it’s probably cleaner to assign the subroutine reference to a lexical variable:

{
    my $foo = sub
    {
        my ($n) = @_;
        print "foo($n)\n";
    };

    $foo->(1);    # valid call
}

$foo->(2);        # invalid call
[download]

This has the advantage of changing the invalid call from a runtime error into a compiletime error.

From Perl v5.18 on you can also use the experimental Lexical Subroutines feature.

Update: Fixed typo in the code snippet.

Hope that helps,