Assume that I have 

  use constant BIRD=>'footchicken';

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and I want to constract a hash reference where BIRD is a key. Obviously I can not do 
  { BIRD => 'Valery' }

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because barewords on the lefthand side of => get quoted. Possible solutions are 
  { BIRD() => 'Valery' }
  { BIRD, 'Valery' }

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both of which I don't like very much (for purely aesthetic reasons). It therefore occured to me that 
  { +BIRD => 'Valery' }

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does not only look nice (for me, that is), but should work. However, it does not. Printing it out with Data::Dumper, i.e. 
use strict;
use warnings;
use Data::Dumper;
use constant { BIRD => 'footchicken' };
print Dumper(+{ +BIRD => 'Valery' });

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displays: 
$VAR1 = {
          'BIRD' => 'Valery'
        };

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This puzzles me. Why do I see BIRD here? Monadic + binds stronger than => and this means that we have +BIRD on the left of =>. This is certainly not a bareword, so it should evaluate as an expression, yielding 'footchicken'. And even in the unlikely case Perl would regard it as bareword here, quoting the beast would be '+BIRD', not 'BIRD'.

-- 
Ronald Fischer <ynnor@mm.st>

In reply to On quoting the lhs of '=>' by rovf

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