in reply to Help with a more precise regex

Not a direct answer to your question, but as a suggestion I wanted to point you in the direction of the Date::Manip module. Often in my scripts which dealt with time/date parsing, this module saved my day. It is able to do a lot of date 'magic' but may require some digging in order to understand :)

Here's a rendition of Ovid's code, but using the Date::Manip module. I agree that using the module for such a simple task may look like an overkill, but I have this feeling your program may have to deal with a lot more date/time manipulation going forward. Even if this is not the case, it's always good to have another way of doing a thing ;-)
use strict; use Date::Manip; foreach (<DATA>) { chomp; next if /^$/; my @delta=split(/:/, ParseDateDelta($_)); my ($day) = $delta[3]; my ($hour) = $delta[4]; print "$_\t=>\tDay: $day\tHour: $hour\n"; } __DATA__ 3d 3d 2h 6h
And the output the script generates is:
3d => Day: 3 Hour: 0 3d 2h => Day: 3 Hour: 2 6h => Day: 0 Hour: 6

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