Really? It shouldn't. 
use strict;
use warnings;

my %op = (
  'toupper' => \*uc{CODE},
  #...
);


print( $op{toupper}->('foo'), "\n" );

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Name "main::uc" used only once: possible typo at a.pl line 5.
Not a CODE reference at a.pl line 10.

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Originally posted as a Categorized Answer.

In reply to Re: How do I get a reference to a builtin function? by ikegami
in thread How do I get a reference to a builtin function? by adram

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