#/usr/bin/perl
use strict;
use warnings;

use constant {
  Undefined => 0,
  Page => 1,
  Index => 2,
};

{my %map = (
  Page => 'mypage',
  Index => 'myindex',
);

use Data::Dumper qw(Dumper);
print Dumper \%map;}

{my %map = (
  Page() => 'mypage',
  Index() => 'myindex',
);

print Dumper \%map;}

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And this is why Perl Best Practices says to use Readonly (with Readonly::XS installed, preferably) instead of constant.

Well, one of the reasons anyway. Another is string interpolation. And I think there are more, though I can't remember them off the top of my head :-)

In reply to Re^3: why doesn't constant work? by Tanktalus
in thread why doesn't constant work? by perl-diddler

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