swift-mirror/stdlib/stdlib.docc/RegexBuilder-collection.md

RegexBuilder

Use an expressive domain-specific language to build regular expressions, for operations like searching and replacing in text.

Overview

Regular expressions, also known as regexes, are a powerful tool for matching patterns in text. Swift supports several ways to create a regular expression, including from a string, as a literal, and using this DSL. For example:

let word = OneOrMore(.word)
let emailPattern = Regex {
    Capture {
        ZeroOrMore {
            word
            "."
        }
        word
    }
    "@"
    Capture {
        word
        OneOrMore {
            "."
            word
        }
    }
}

let text = "My email is my.name@example.com."
if let match = text.firstMatch(of: emailPattern) {
    let (wholeMatch, name, domain) = match.output
    // wholeMatch is "my.name@example.com"
    // name is "my.name"
    // domain is "example.com"
}

Topics

Components

• Swift/RegexComponent
• RegexBuilder/CharacterClass
• RegexBuilder/Anchor
• RegexBuilder/Lookahead
• RegexBuilder/NegativeLookahead
• RegexBuilder/ChoiceOf

Quantifiers

• RegexBuilder/One
• RegexBuilder/Optionally
• RegexBuilder/ZeroOrMore
• RegexBuilder/OneOrMore
• RegexBuilder/Repeat
• RegexBuilder/Local

Captures

• RegexBuilder/Capture
• RegexBuilder/TryCapture
• RegexBuilder/Reference

Builders

• RegexBuilder/RegexComponentBuilder
• RegexBuilder/AlternationBuilder