To append a match efficiently in Vim :g/---/s/---/X/

Question

How can you refer to the match in the command g in Vim?

I would like to put X after the match without replacing the match. For instance, in the following command without writing the create_title twice.

:g/create_title/s/create_title/X/

You should get

create_titleX

by running the command to

create_tile

Answer 1

:%s/\(create_title\)/\1X/g

works for me. (if I understand your question correctly).

Answer 2

I'm not sure why you need the g portion of the command - the substitute will only act on matching lines. Here's what you're looking for:

:%s/create_title/&X/

The & represents the entire text which was matched.