Sticking an evaled use constant in a BEGIN block would seem to meet your requirement, and avoid those nasty typeglobs: 
#!/usr/bin/perl
use strict;
use warnings;

my @num_to_name;
BEGIN {
    @num_to_name = qw(FOO BAR);
    eval "use constant $num_to_name[$_] => $_" for 0 .. $#num_to_name;
}

print "FOO-->", FOO(), "-->", $num_to_name[FOO];

[download]

I've assumed your names are necessarily 1:1 and adjacent integers starting at 0 - this is what your code seems to do. You could do something with hashes instead for more flexibility.

In reply to Re: Crazy constant question... by kennethk
in thread Crazy constant question... by pileofrogs

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