Greedy matching

Q: How deeply does Tiny Python Projects: Learn coding and testing with puzzles and games cover greedy matching?

Explains greedy, non-greedy, and delimiter-excluding patterns with interactive examples, but does not cover regex-engine internals.

As explained in 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.

Greedy matching makes a regular-expression quantifier such as * or + consume as many characters as possible while still allowing the pattern to match. With <.+>, the dot spans multiple placeholders and stops at the final >, not the first. section 17.1.1

Matching angle-bracket placeholders

Given `The quick <adjective> <noun> jumps ...`, `re.search('(<.+>)', text)` returns the entire span from `<adjective>` through the final `>`. Use `<.+?>` to stop at `<adjective>`, or `<[^<>]+>` to exclude both angle brackets from the contents and preserve balanced pairs. section 17.1.1

Control the match when a greedy quantifier crosses the intended delimiter:

Append `?` to make `+` or `*` non-greedy, selecting the shortest possible match. section 17.1.1
Prefer a negated character class such as `[^<>]+` when the contents must not contain either delimiter. section 17.1.1

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The Well-Grounded Rubyist, Fourth EditionA greedy quantifier matches as many repetitions as possible while still allowing the remainder of the regular expression to match.

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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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