Temperature Module

temp_convert.pl

#!/usr/bin/perl -w
use strict;
use warnings;
use Temperature;

my $arg = $ARGV[0] || '-c20';
if ($arg =~ /^\-(c|f)((\-|\+)*\d+(\.\d+)*)$/) {
	my ($deg, $num) = ($1, $2);
	my ($in, $out) = ($num, $num);
	if ($deg eq 'c') {
		$deg = 'f';
		$out = Temperature::c2f($num);
	} else {
		$deg = 'c';
		$out = Temperature::f2c($num);
	}
	$out = sprintf('(%0.2f)', $out);
	$out =~ s/^((\-|\+)*\d+)\.0+$/$1/;
	print "$out $deg\n";
} else {
	print "Usage: $0 -[c|f]num\n";
}
exit;

Temperature.pm

package Temperature;
use strict; use warnings;

sub f2c {
	my $f = shift;
	my $c = (5/9) * ($f - 32);
	return $c;
}
sub c2f {
	my $c = shift;
	my $f = (9/5 * $c)  + 32;
	return $f;
}

1;