check out perlsyn and perlop (in particular the comparison operators) 
my $num = $_ = 4;
if($num >= 0) {
   die "$num is positive";
} else {
   die "$num is negative (but we already knew that)";
}

# or even ;)
my $num = $_ = -4;
if(substr($num,0,1,) eq '-') {
   die "I, $num, feel so negative today";
} else {
   die "$num says 'Things are looking up'";
}

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In reply to Re: how do i test a number negative or positive? by PodMaster
in thread how do i test a number negative or positive? by dswimboy

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