If all your trying to do is extract those specific characters, then this might work for you: 
use strict;
use warnings;


while (<DATA>) {
print "$1\n" if $_ =~ /(!=|<=|>=|==)/;
    }

__DATA__
$this <= $that
$this lt $that
$this >= $that
$this gt $that
$this != $that
$this ne $that
$this == $that
$this eq $that

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I do suggest you read up on Regular Expressions as it will help you out tremendously on your journey :)

In reply to Re: How to extract special charachetrs like <=, >= != from string by james28909
in thread How to extract special charachetrs like <=, >= != from string by gjoshi

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