Return indices of all regex occurrences in a string in Ruby

Question

How do I get an array of indices (or positions) of all occurrences of a regex in a string?

example_string= "hello how are you?

I would like to get array [1,12] for regexp /e/

+3

CoupDeMistral Jul 19 15 at 22:22

2 answers

This is a great variation on @ Zoren's answer:

example_string = "hello how are you?"

example_string.gsub(/e/).with_object([]) { |_,a| a << Regexp.last_match.begin(0) }
 #=> [1, 12]

+4

Cary swoveland Jul 20. '15 at 1:20

Zoran · Accepted Answer · 2015-07-19T22:32:12+0000

Here's one approach for getting an array of match indices:

example_string = "hello how are you?"

example_string.enum_for(:scan, /e/).map { Regexp.last_match.begin(0) }

# => [1, 12]

Hope it helps!