Question

I’m trying to pull the user_id from a foursquare URL, like this one:

 https://foursquare.com/user/99999999

The following regex pulls exactly what I need (a series of numbers that terminate with the end of the line):

\d+$

However, I’m not sure how to set a string equal to the matched characters. I’m aware of sub and gsub, but those methods substitute a matched string for something else.

I’m looking for a way to specifically pull the section of a string that matches my regex (if it exists)

Answer 1

I like to use the return of match():

Anything wrapped in a capture () in the regex, gets assigned to the match result array

"https://foursquare.com/user/99999999".match(/(\d+)\z/)[1] #=> "99999999"