Regex matching multiple lines multiple times

Question

I have a string like this:

Name: John Doe

Age: 23

Primary Language: English

Description: This is a multiline
description field that I want 
to capture

Countr         


        

Answer 1

Here's one solution: http://rubular.com/r/uDgXcIvhac.

    \s*([^:]+?)\s*:\s*(.*(?:\s*(?!.*:).*)*)\s*

Note that I've used a negative lookahead assertion, (?!.*:). This is the only way you can check that the next line doesn't look like a new field, and at the same time continue where you left off. (This is why lookaheads and lookbehinds are known as zero-width assertions.)

EDIT: Removed bit about arbitrary-width lookaheads; I was mistaken. The above solution is fine.