Instance Methodswift 6.1.2_StringProcessing

    prefixMatch(in:)

    Returns a match if this regex matches the given string at its start.

    iOS
    16.0+
    macOS
    13.0+
    tvOS
    16.0+
    watchOS
    9.0+
    func prefixMatch(in string: String) throws -> Regex<Output>.Match?
    Mangled symbol
    s17_StringProcessing5RegexV11prefixMatch2inAC0E0Vyx_GSgSS_tKF What are these?
    FNV24 hash
    5OH8I

    Parameters

    string

    The string to match this regular expression against.

    Returns

    The match, if this regex matches at the start of string; otherwise, nil.

    Call this method if you want the regular expression to succeed only when it matches only at the start of the given string. This example uses prefixMatch(in:) and a regex that matches a title-case word to search for such a word at the start of different strings:

    let titleCaseWord = /[A-Z][A-Za-z]+/

if let wordMatch = try titleCaseWord.prefixMatch(in: "Searching in a Regex") {
    print(wordMatch.0)
} else {
    print("No match.")
}
// Prints "Searching"

if let wordMatch = try titleCaseWord.prefixMatch(in: "title case word at the End") {
    print(wordMatch.0)
} else {
    print("No match.")
}
// Prints "No match."

    The prefixMatch(in:) method can throw an error if this regex includes a transformation closure that throws an error.