Re: Testing private methods a no-no?

FYI: Did you know you can create truly private subs in Perl?

# create a block to isolate the sub
{
    local *foo = sub { print "foo\n"; };
    # this works
    foo();
}
# this does not work
foo();
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Comment on Re: Testing private methods a no-no? Download Code

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Re^2: Testing private methods a no-no?
by Athanasius (Cardinal) on May 22, 2016 at 05:50 UTC

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
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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,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

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[d/l]

Re^2: Testing private methods a no-no?
by Anonymous Monk on May 20, 2016 at 21:01 UTC

that was random

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