Regular expressions (regex) are patterns used to match character combinations in strings. Here is a cheat sheet for common regex patterns and their meanings¹².

Character Classes

• [abc]: Matches any one of the characters a, b, or c.

• [^abc]: Matches any character except a, b, or c.

• [a-z]: Matches any character from a to z.

• \d: Matches any digit (equivalent to [0-9]).

• \D: Matches any non-digit.

• \w: Matches any word character (alphanumeric + underscore).

• \W: Matches any non-word character.

• \s: Matches any whitespace character (spaces, tabs, line breaks).

• \S: Matches any non-whitespace character.

Anchors

• ^: Matches the beginning of a string.

• $: Matches the end of a string.

• \b: Matches a word boundary.

• \B: Matches a non-word boundary.

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