Word.ws English Dictionary

positive lookahead

positive lookahead noun: the analysis of the subsequent characters presence before the regular expression is matched (symbol: ?=).

Noun

positive lookahead (countable and uncountable, plural positive lookaheads)

  1. (regular expressions) The 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

Forms of positive lookahead

pluralpositive lookaheads

Origin of positive lookahead

From positive + lookahead.

Questions about positive lookahead

What does positive lookahead mean?
Positive lookahead means the analysis of the subsequent characters presence before the regular expression is matched (symbol: ?=).
What part of speech is positive lookahead?
Positive lookahead is a noun.
What is the plural of positive lookahead?
The plural of positive lookahead is positive lookaheads.

Words near positive lookahead in the dictionary

  1. positive law
  2. positive laws
  3. positive linear functional
  4. positive linear functionals
  5. positive logic
  6. positive lookahead
  7. positive lookaheads
  8. positive lookaround
  9. positive lookbehind
  10. positive material identification
  11. positive measure

Source and license

Adapted from Wiktionary: positive lookahead (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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