When I am running the below code , I am getting the following error :
Use of uninitialized value $_ in pattern match (m//) at main.pl line 10,
<STDIN> line 5 (#1)
(W uninitialized) An undefined value was used as if it were already
defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
To suppress this warning assign a defined value to your variables.

 
#! /usr/bin/perl

use strict;
use warnings;
use diagnostics;

chomp( my @input = <STDIN> );

foreach my $line (@input){
    if ( /fred/ ){
        print "Matched : $line";
    }
    
}

[download]

But when I replace $line with $_ , the code is running absolutely fine , I know I am doing some conceptual error , kindly help me fix it

In reply to Beginner in perl : Use of uninitialized value by Perl_Programmer1992

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