Terbium-135
Given this (TeX) string (with a newline at the end):
\fill[cardbackground, rounded corners=2pt] (0,0) rectangle (\cardwidth,\cardheight);
I am able to match with this regex:
~r/.*(cardbackground).*;\n/
How do I replace only the first group match (which is cardbackground in this case) using something like:
Regex.replace(~r/.*(cardbackground).*;\n/, source, "{RGB}{245,245,245}")
Looking at Regex — Elixir v1.20.2 is of not much help (to me).
What do I miss?
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NobbZ
As you didn’t share any code, I have to ask whether you tried
global: false?al2o3cr
If you only want to replace
cardbackground, only match that:If you want to look for a pattern but not include it in the match, you can use a positive lookahead assertion:
This still only matches
cardbackgroundalone, so that’s the only part that gets replaced. The assertion looks for;\nat the end of the line.Terbium-135
Yes. Positive look ahead might work.
Reason for changing only a single group within a match is:
There might be a small chance that
cardbackgroundcan appear within another context more than one time and matching just this is not enough.But I will be able to match the surrounding text using one or two lookaheads
Terbium-135
Just a
global: falsemight be not sufficient in this case.Anyway: Thank you both for chiming in