Hello Violet, and welcome to the Monastery!

Although there is nothing wrong with your approach, a more idiomatic or “Perlish” way to do this would be to use a hash for the look-up. Here’s a little script to illustrate:

#! perl
use strict;
use warnings;

my @list   = qw( Wilma Betty );
my %lookup = map { $_ => undef } @list;

while (my $line = <DATA>)
{
    my @fields = split /\s+/, $line;

    next unless defined $fields[1];

    print $line if exists $lookup{$fields[1]};
}

__DATA__
Fred    Wilma   Pebbles     Dino
Barney  Betty   Bamm-Bamm
Homer   Marge   Bart        Lisa    Maggie
George

[download]

Output:

23:18 >perl 1015_SoPW.pl
Fred    Wilma   Pebbles     Dino
Barney  Betty   Bamm-Bamm

23:18 >

[download]

Please note the line:

use strict;

[download]

Get in the habit of including this in all your scripts, and it will save you a lot of debugging time in the long run. (Essentially, it just means you will need to put my before each variable the first time that variable is used in the script.)

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Looping in a Loop by Athanasius
in thread Looping in a Loop by Violet

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