cours/vim regex lookaround.md

alias

alias
vim regex lookahead vim regex lookbehind vim regex lookaround lookahead lookbehind lookaround

up:: vim regex title:: "before and after matches" #s/informatique

---

Allows to match pattern after (lookahead) or before (lookbehind) the current pattern.

Quick reference

• \zs starts the selection (everything before is searched for but not matched)
• \ze stop the selection (everything after is searched for but not matched)

	positive	negative
lookahead	@=	@!
lookbehind	@<=	@<!

Exemples

[!example] president (not (Macron|Hollande)) To match President if it is not President Macron or President Hollande. Note that the match will select only President (else the regex is obvious). President\(Macron\|Hollande\)\@! Or, with verymagic mode \vPresident(Macron|Hollande)@!

[!example] python attributes, but not of self Match any python attribute (a word after a dot), except attributes of self (attributes of an object from the object itself) \(self\)\@<!\.\zs\w\+ or, with verymagic mode \v(self)@<!.\zs\<+