English Dictionary

positive lookahead

noun

(regular expressions) The analysis of the subsequent characters presence before the regular expression is matched (symbol: ?=).

Positive lookahead is a useful feature in regular expressions.

意味（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.