Dear monks, I constructed this simple program that will show what is the problem. 
#!/usr/bin/perl

use strict;
use warnings;

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

print Dumper( $] );
 # Prints "5.010000" on my version of perl
print Dumper( $Module::CoreList::version{ $] } );
 # Prints undef
print Dumper( $Module::CoreList::version{ "$]" } );
 # Prints undef
print Dumper( $Module::CoreList::version{ 5.010000 } ); 
 # Prints "correct" list ...

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I don't understand why accessing hash with $] is different from accessing with it's value (in my case 5.010000)?

In reply to Problem with accessing hash Module::CoreList::version with $] by XooR

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