please do NOT use $a and $b since this variables are reserved for use with sort. you can use the eval call: 
use strict;

my $n1= 10;
my $n2= 20;
my $operator= "==";

my $expr = "$n1 $operator $n2";
my $erg = eval $expr;
die if ($@);

if ($erg) {
    print "true\n";
} else {
    print "false\n";
}

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In reply to Re: Dynamic operators by kabel
in thread Dynamic operators by Preceptor

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