CharacterSet.swift

    /// Returns a character set containing the characters in Unicode General Category Cc and Cf.
    public static var controlCharacters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category Zs and `CHARACTER TABULATION (U+0009)`.
    public static var whitespaces: CharacterSet { get }

    /// Returns a character set containing characters in Unicode General Category Z*, `U+000A ~ U+000D`, and `U+0085`.
    public static var whitespacesAndNewlines: CharacterSet { get }

    /// Returns a character set containing the characters in the category of Decimal Numbers.
    public static var decimalDigits: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category L* & M*.
    public static var letters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category Ll.
    public static var lowercaseLetters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category Lu and Lt.
    public static var uppercaseLetters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category M*.
    public static var nonBaseCharacters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Categories L*, M*, and N*.
    public static var alphanumerics: CharacterSet { get }

    /// Returns a character set containing individual Unicode characters that can also be represented as composed character sequences (such as for letters with accents), by the definition of "standard decomposition" in version 3.2 of the Unicode character encoding standard.
    public static var decomposables: CharacterSet { get }

    /// Returns a character set containing values in the category of Non-Characters or that have not yet been defined in version 3.2 of the Unicode standard.
    public static var illegalCharacters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category P*.
    public static var punctuationCharacters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category Lt.
    public static var capitalizedLetters: CharacterSet { get }

    /// Returns a character set containing the characters in Unicode General Category S*.
    public static var symbols: CharacterSet { get }

    /// Returns a character set containing the newline characters (`U+000A ~ U+000D`, `U+0085`, `U+2028`, and `U+2029`).
    public static var newlines: CharacterSet { get }