I don't get warnings from other closures.

It is because the declaration of $color is conditional. 

 my $color   = shift                 if @_;

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If you only pass 1 parameter to the outer sub, $color will never be declared, so won't (can't) be available to the inner sub.

If you just dropped the conditional, the code would work properly. If you shift a value from an empty array into a scalar it will be set to undef which will work fine in the inner sub conditional.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Closure warning with Perl 5.14? by BrowserUk
in thread Closure warning with Perl 5.14? by BerntB

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