Re: String/Numeric Manipulation

[Random_Walk]

The while test on the value of days is made after the conversion to seconds is done so when you enter q you are trying to convert it to seconds. you could do a few things, here is one that keeps a while loop...

#!/usr/local/bin/perl -w
use strict;

while (1) {
    print
"Please enter a single positive integer that represents a number of da
+ys, that you wish to convert into seconds. ,(enter q to quit): ";

    chomp (my $days = <STDIN>);
    $days =~ s/\+//;    # allow them to enter +12

    if ($days eq "q") {
        last;
    } elsif (($days =~ /[^\d]/) or ($days eq "")) {
        # days contains an non digit character or is empty
        print "\n!!! You must enter a positive integer.\n\n";
    } else {
        my $seconds = $days * 86400;
        my $plural = ($days == 1) ? '' : 's';
        print "\n$days day$plural = $seconds seconds.\n\n";
    }
}

print "Goodbye\!\n\n";

update to catch entry of 0

Change the elsif check to this if you want to prevent them from entering zero days

    } elsif (($days =~ /[^\d]/) or (not $days)) {

Cheers,
R.

[Elgon]

Random_Walk,

A minor nit. If I've understood the code correctly, you've used a substitution...

$days = s/+//;

...where a transliteration would be "better"...

$days = tr/+//d;    # Note transobliteration modifier

...and a lot faster (not that this is really an issue in this case.)Unless you wanted to allow only a leading + in which case...

$days = s/^+//;

Elgon

[Random_Walk]

You are right tr would have been more efficient for what I did but I really should have put s/^+//; to follow the principle of least surprise so that 2+3 would be rejected rather than converted to 23

Cheers,
R.