RegexPattern

struct RegexPattern : struct RegexPattern

struct [source] ¶

struct [source] ¶

struct RegexPattern

Bases:

• Sendable
• Hashable
• Decodable
• Encodable
• SendableMetatype
• Equatable

A compiled regular expression with bounded memory and matching work.

The supported dialect has literals, escaped punctuation, , ^, $, grouping, noncapturing grouping, alternation, *, +, ?, counted repetitions, character classes and ranges, and ASCII \d, \s, and \w shorthands. Lookaround and backreferences are rejected.

Matching consumes Swift extended grapheme clusters. Literal equality uses Swift Character equality, including canonical equivalence. With Options/caseInsensitive, each character is compared through locale-independent lowercased() values; full multi-character case folding is not performed, so ss does not match ß. Dot excludes line terminators.

Swift's own Regex cannot take this job. Its matcher backtracks — on Swift 6.2, (a+)+b against twenty as takes 78 seconds — and a match is synchronous, so the deadline Server/waitForOutput(in:matching:stoppingAt:requiringFreshOutput:timeout:tailLimit:) races cannot interrupt one that has started. A pattern here is bounded before it runs, which is also what makes one safe to accept from a client.

Members

• !=(_:_:) function Returns a Boolean value indicating whether two values are not equal.
• ==(_:_:) function Returns a Boolean value indicating whether two values are equal.
• containsMatch(in:maximumWork:) method Returns whether the expression occurs in input before its positive work budget.
• encode(to:) method Encodes this value into the given encoder.
• hash(into:) method Hashes the essential components of this value by feeding them into the given hasher.
• init(_:options:) method Compiles a bounded regular expression.
• init(from:) method Creates a new instance by decoding from the given decoder.
• defaultMaximumWork property
• maximumCompiledStates property
• maximumInputUTF8Bytes property
• maximumNesting property
• maximumRepetition property
• maximumSourceUTF8Bytes property
• options property Options applied during matching.
• source property The source form preserved for encoding and diagnostics.
• Options struct Matching options encoded with the pattern.