Meanings
nounpositive lookahead (countable and uncountable, plural positive lookaheads)
plural positive lookaheads
- countableuncountableregular expressionsThe analysis of the subsequent characters presence before the regular expression is matched (symbol: ?=).
Negative lookahead works just like positive lookahead, except that whereas positive lookahead matches when the regex inside the lookahead matches, negative lookahead matches when the regex inside the lookahead failed to match.
2012 August, Jan Goyvaerts, Steven Levithan, Regular Expressions Cookbook
Origin
Cite this entry
APA
positive lookahead. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/positive%20lookahead
MLA
“positive lookahead.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/positive%20lookahead. Accessed November 4, 2026.
Chicago
WatkinsX Dictionary, s.v. “positive lookahead,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/positive%20lookahead.
Source: positive lookahead on Wiktionary, CC BY-SA 4.0.