Ruby gsub : is there a better way

Question

I need to remove all leading and trailing non-numeric characters. This is what I came up with. Is there a better implementation.

puts s.gsub(/^\D+/,'').gsub(/\D+$/,'')

Answer 1

Instead of eliminating what you don't want, it's often clearer to select what you do want (using parentheses). Also, this only requires one regex evaluation:

s.match(/^\D*(.*?)\D*$/)[1]

Or, this convenient shorthand:

s[/^\D*(.*?)\D*$/, 1]