It's a parsing issue. You'll find this works: 
map2 sub { print "$a $b" }, qw[A B C D];

[download]
Update: 
$ perl -v

This is perl, v5.6.1 built for i386-linux

Makeshifts last the longest.

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

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