You should be able to do the whole thing including file_C in one pass of file_A. 

#!perl -slw
use strict;
use vars qw[$NEW_A];
use Data::Dumper;
use Inline::Files '-backup';
local $,=', ';

my %b = map{ (
                '1'.$_->[0] => 1,
                '4'.$_->[1] => 1,
        ) }
        map{ [ (split':')[0,3] ] } <FILE_B>;

my %c = map{ $_ => 1 } map{ (split':')[2] } <FILE_C>;

#print Dumper \%b, \%c;

open NEW_A, "> $NEW_A" or die $!;

while(<FILE_A>) {
    chomp;
    my @fields = split':';
    print( "Removing '$_' from FILE_A because field 1:'$fields[0]' not
+ in FILE_B"),
        next if !exists $b{ '1'.$fields[0] };
    print( "Removing '$_' from FILE_A because field 4:'$fields[3]' not
+ in FILE_B"),
        next if !exists $b{ '4'.$fields[3] };
    print( "Removing '$_' from FILE_A because field 3:'$fields[2]' not
+ in FILE_C"),
        next if !exists $c{ $fields[2] };
    print NEW_A $_, $/;
}

__FILE_A__
1:*:Z:A:*
2:*:Y:B:*
3:*:X:C:*
4:*:Z:D:*
5:*:Y:E:*
6:*:X:F:*
7:*:T:G:*
__FILE_B__
1:*:*:A:*
2:*:*:B:*
3:*:*:C:*
4:*:*:D:*
5:*:*:E:*
6:*:*:F:*
__FILE_C__
*:*:Z:*:*
*:*:Y:*:*
*:*:T:*:*
__NEW_A__
1:*:Z:A:*
2:*:Y:B:*
4:*:Z:D:*
5:*:Y:E:*

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Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.

In reply to Re: hash jerkin by BrowserUk
in thread hash jerkin by rerunn

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