Anchors and Boundaries

Anchors and Boundaries

Regular expressions often need to anchor matches to specific positions within the text, such as the beginning or end of a line, or even word boundaries. These special characters, known as anchors, do not match any character themselves but assert that the current position in the string matches a certain condition.

Start and End of String Anchors

The caret ^ and dollar sign $</code> are the most common anchors.</p><ul><li><strong><code>^</code></strong>: Matches the start of the string.</li><li><strong><code>$: Matches the end of the string.

Word Boundaries

The sequence \b matches a word boundary—a position where a word character (\w) is not followed or preceded by another word-character, such as at the beginning or end of a word.

Conversely, \B matches a non-word boundary.