Regex Without Tears

What a Regular Expression Is

A regex can fit a large amount of syntax into a short line:

This example is easier to read after it is split into tokens. The ^ and $ constrain positions, bracketed expressions describe allowed characters, + means repetition, and @ is literal text. This chapter first defines the values involved in matching; later chapters explain each token.

An excerpt from the working manuscript. Read the illustrated pages or download the complete sample chapter.