How do I use a part of the matched text in regex for Sublime Text, in the replacement?

Question

If I have

width: 12px 0;
width: 24px 0;

how can I use regex to replace it with

width: 12px 0px;
width: 24px 0px;

While keeping the first number intact?

I am using Sublime Text that uses Python PCRE for regex. I tried searching Google and Bing and reading the Sublime Text documentation and I couldn't find anything helpful. Using :[0-9]*px 0; and :${m}px 0px; doesn't work.

Answer 1

You could use

(:\h*\d+px\h+\d+);

• ( Capture group 1
  • :\h*\d+px Match : optional spaces and 1+ digits followed by px
  • \h+\d+ Match 1+ spaces and 1+ digits
• ); Close group and match ;

And replace with the first group followed by px; like $1px;

Regex demo

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Without using a capture group, this could be another option using \K to forget what is matched so far, and replace with px;

:\h*\d+px\h+\d+\K;

Regex demo