Regular expression for word not in specific latex command

Question

I am looking for a regular expression which will match all occurrences of foo unless it is in a \ref{..} command. So \ref{sec:foo} should not match.

I will probably want to add more commands for which the arguments should be excluded later so the solution should be extendable in that regard.

There are some similar questions trying to detect when something is in parenthesis, etc.

The first has an interesting solution using alternatives: \(.*?\)|(,) the first alternative matches the unwanted versions and the second has the match group. However, since I am using this is in a search&replace context I cannot really use match groups.

What language are you using? – Pushpesh Kumar Rajwanshi Apr 29 '19 at 09:54 — Pushpesh Kumar Rajwanshi, Apr 29 '19 at 09:54

score 3 · Answer 1 · answered Apr 29 '19 at 09:58

3

Finding a regex for what you want will need variable length look behind which is only available with very limited languages (like C# and PyPi in Python) hence you will have to settle with a less than perfect. You can use this regex to match foo that is not within curly braces as long as you don't have curly nested curly braces,

\bfoo\b(?![^{}]*})

This will not match a foo inside \ref{sec:foo} or even in somethingelse{sec:foo} as you can see it only doesn't match a foo that isn't contained in a curly braces. If you need a precise solution, then it will need variable length look behind support which as I said, is available in very limited languages.

Regex Demo

answered Apr 29 '19 at 09:58

Pushpesh Kumar Rajwanshi

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Yeah, that's what the other answers suggest as well but it's not really what I want because I want to make sure I know all the latex commands in which it appears as a parameter. – Pumpkin Apr 29 '19 at 11:14
In that case, I'll suggest you to go for a custom parser. Safe and efficient. – Pushpesh Kumar Rajwanshi Apr 29 '19 at 11:15
I'm not sure writing a custom parser for latex can be done in an efficient way. ;) – Pumpkin Apr 29 '19 at 11:54
I don't know about `latex` but if you can give me some idea, perhaps I can try helping you. Like, show me some sample data and your expected output out of that data? – Pushpesh Kumar Rajwanshi Apr 29 '19 at 11:58

Regular expression for word *not* in specific latex command

1 Answers1

Regular expression for word not in specific latex command