What alternative to capture groups should I use in VimScript?

Question

I understand that Vim does not support regex capture groups. The problem I am trying to solve is being able to easily capture parts of lines. For example, given the following line of python source code:

def is_string(s, *args):

I would like to do something equivalent to using the following PCRE regex, which captures the function's name:

'^def (\w+) ?\(.*'

(the capture group here would match is_string

What would be the idiomatic way in VimScript to specify a regex pattern for what part of a line I am trying to match?

Answer 1

I understand that Vim does not support regex capture groups

I'm not sure where you got that idea from. Vim-regex most definitely supports capture groups. It wouldn't be very useful without them...

Your regex is already pretty much right. Just a couple differences with which characters need to be escaped or not:

^def \(\w\+\) \?(.*

Or if you want to use very magic,

\v^def (\w+) ?\(.*