Question

I keep getting into situations where I end up making two regular expressions to find subtle changes (such as one script for 0-9 and another for 10-99 because of the extra number)

I usually use [0-9] to find strings with just one digit and then [0-9][0-9] to find strings with multiple digits, is there a better wildcard for this?

ex. what expression would I use to simultaneously find the strings
6:45 AM and 10:52 PM

Answer 1

You can specify repetition with curly braces. [0-9]{2,5} matches two to five digits. So you could use [0-9]{1,2} to match one or two.

[0-9]{1,2}:[0-9]{2} (AM|PM)

I personally prefer to use \d for digits, thus

\d{1,2}:\d{2} (AM|PM)