Greedy matching
Greedy matching is regular-expression behavior in which a quantifier matches as much text as possible while still allowing the overall pattern to match.
The Well-Grounded Rubyist, Fourth Edition
A greedy quantifier matches as many repetitions as possible while still allowing the remainder of the regular expression to match.
- How it is used
- Uses greedy and non-greedy quantifiers to control how regular expressions consume repeated characters.
- How deep it goes
- Explains default greediness, lazy modifiers, captures, and backtracking, stopping short of broader regexp-engine implementation.
- Examples
- Demonstrates digit runs, exclamation-delimited strings, and MatchData captures showing backtracking.
- What you can do after
- Diagnose regexp matches by predicting greedy consumption, applying lazy modifiers, and inspecting captures after backtracking.
Read how The Well-Grounded Rubyist, Fourth Edition explains greedy matching →
Tiny Python Projects: Learn coding and testing with puzzles and games
A regular-expression matching behavior in which a quantifier selects the longest possible substring that still permits the pattern to match.
- How it is used
- Uses greedy matching while extracting angle-bracket placeholders from Mad Libs input.
- How deep it goes
- Explains greedy, non-greedy, and delimiter-excluding patterns with interactive examples, but does not cover regex-engine internals.
- Examples
- Demonstrates `<.+>`, `<.+?>`, and `<[^<>]+>` against placeholder text and unbalanced brackets.
- What you can do after
- Diagnose/debug with Python regular expressions by identifying overmatching and choosing non-greedy or delimiter-excluding patterns.
Related concepts
- BERTScoreimplemented by · BERTScore is an automatic text-generation evaluation metric that compares candidate and reference texts using contextual representations of their tokens.
- non-greedy quantifiercontrasts with · A non-greedy quantifier matches the fewest repetitions that allow the entire regular expression to match.
- regular expressionuses · A formal pattern notation that describes sets of strings and enables text to be matched, searched, extracted, or transformed.
- quantifierkind of · A regular-expression quantifier is syntax that specifies how many times a preceding pattern element may or must match.
- prefixaddresses · A prefix is an initial component or sequence of a larger word, string, name, path, or other structured value.
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