It looks like a bug to me, somehow related to qw, not the prototype. You can supply a list as an argument, just not one generated by qw.

map2{ print $a $b; } 'A', 'B', 'C', 'D'; #works fine!
map2{ print $a $b; } map {$_} qw{A B C D}; #works
map2{ print $a $b; } qw{A B C D}; #doesn't compile (as you said)

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I don't know if this is ActiveState specific or 5.6 specific - the only 5.6 I have is ActiveState

In reply to Re: Problem emulating built-ins like map and grep. by jsprat
in thread Problem emulating built-ins like map and grep. by BrowserUk

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