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in reply to Problem with accessing hash Module::CoreList::version with $]

Apparently, this special variable is only a string in perl 5.10, even though the documentation seems to suggest that it be a floating point number. If you use $]+0 in your example, it'll work (which is kind of strange because ordinary hash keys are converted to strings anyway, but in this case I think we are dealing with a tied hash).

% perl5.8.8 -we 'use Devel::Peek; Dump $]' 
SV = PVNV(0x9f664d0) at 0x9f63ed0            
  REFCNT = 1
  FLAGS = (NOK,POK,READONLY,pNOK,pPOK)
  IV = 0
  NV = 5.008008                       #  <-- in 5.8 it was a number
  PV = 0x9f7d250 "5.008008"\0
  CUR = 8
  LEN = 12

% perl5.10.0 -we 'use Devel::Peek; Dump $]'  
SV = PV(0x9457198) at 0x946a610
  REFCNT = 1
  FLAGS = (POK,READONLY,pPOK)
  PV = 0x945e538 "5.010000"\0
  CUR = 8
  LEN = 12

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Re^2: Problem with accessing hash Module::CoreList::version with $]
by XooR (Beadle) on Apr 24, 2009 at 10:39 UTC
    betterworld sad:
    Apparently, this special variable is only a string in perl 5.10, even though the documentation seems to suggest that it be a floating point number. If you use $]+0 in your example, it'll work (which is kind of strange because ordinary hash keys are converted to strings anyway, but in this case I think we are dealing with a tied hash).
    Thanx, that's solved it. I will read about tied hashes and see if this is a problem.
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Re^2: Problem with accessing hash Module::CoreList::version with $]
by Anonymous Monk on Apr 24, 2009 at 10:13 UTC
    Actually that makes no difference, works just fine in 5.10. His problem is he expect Data::Dumper output to be identical. Maybe if he use $Data::Dumper::Sortkeys ... or this 
    #!/usr/bin/perl

use strict;
use warnings;

use Module::CoreList;
use Data::Dumper;

$Data::Dumper::Sortkeys=1;
print Dumper(
    $Module::CoreList::version{ $] },

    $Module::CoreList::version{ "$]" },
    $Module::CoreList::version{ 5.010000 }
);
__END__
$VAR1 = {
          'AnyDBM_File' => '1.00',
.....
        };
$VAR2 = $VAR1;
$VAR3 = $VAR1;

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