While trying to come up with an elegant solution to File Parsing and Pattern Matching I am completely stuck on something I have no explanation for. Here is the solution I came up with: 

use strict;
use warnings;
use Data::Dumper;

my %results = do
{
        local $/ = ''; # paragraph mode
        map { /TYPE (\S+)/ => 
                    { 
                            'cause'  => (/CAUSE (\S+)/ ?$1:'UNDEF'), 
                            'effect' => (/AFFECT (\S+)/?$1:'UNDEF'),
                    }
        } <DATA>;
};
print Dumper \%results;

__DATA__
TYPE VALUE1 EQUALS MAIN
CAUSE FAIL
AFFECT ERROR
ENDTYPE

[download]

shortening Mark.Allan's data to illustrate the point. While I am unable to spot any flaws in my logic it prints the following: 

$VAR1 = {
          'VALUE1' => {
                        'effect' => 'ERROR',
                        'cause' => 'ERROR'   # instead of 'FAIL'
                      }
        };

[download]

If I change the order of 'cause' and 'effect' in the code above I get 'FAIL' twice.

How can this be? And how can it be fixed? (Must be a case of Perl punishing my vanity...)

In reply to Unexpected matching results by hdb

Title:
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