Creating a regular expression object from a String literal

regex.swift

class Regex {
    let pattern: String
    let options: NSRegularExpressionOptions!

    private var matcher: NSRegularExpression {
        return NSRegularExpression(pattern: self.pattern, options: nil, error: nil)
    }

    required init(pattern: String, options: NSRegularExpressionOptions = nil) {
        self.pattern = pattern
        self.options = options
    }

    func match(string: String, options: NSMatchingOptions = nil) -> Bool {
        return self.matcher.numberOfMatchesInString(string, options: options, range: NSMakeRange(0, string.utf16Count)) != 0
    }
}

extension Regex: StringLiteralConvertible, ExtendedGraphemeClusterLiteralConvertible {
    typealias ExtendedGraphemeClusterLiteralType = StringLiteralType

    class func convertFromExtendedGraphemeClusterLiteral(value: ExtendedGraphemeClusterLiteralType) -> Self {
        return self(pattern: value)
    }

    class func convertFromStringLiteral(value: StringLiteralType) -> Self {
        return self(pattern: value)
    }
}

// MARK: -

protocol RegularExpressionMatchable {
    func match(regex: Regex) -> Bool
}

infix operator =~ { associativity left precedence 130 }
func =~<T: RegularExpressionMatchable> (left: T, right: Regex) -> Bool {
    return left.match(right)
}

extension String: RegularExpressionMatchable {
    func match(regex: Regex) -> Bool {
        return regex.match(self)
    }
}


"foo" =~ "f" // true

Awesome! Why isn't this part of Swift? ;-)

I'm assuming you intended to pass self.options to the NSRegularExpression c'tor when creating the matcher.

Thank you! Great! Your code was working in my project until i (to bad) updated to Xcode 6.1, now i am getting 3 errors in extension Regex: Type 'Regex' does not confirm to protocol 'StringLiteralConvertible'; to protocol 'Unicode ScalarLiteralConvertible'; to protocol 'ExtendedGraphemeClusterLiteralConvertible'.

I've taken this and updated it for the current version of Xcode, and also made it so you can use an actual NSRegularExpression as the RHS. See https://gist.github.com/grosch/d3daeec1eefcf1614442

hi I update it for swift 1.2 https://gist.github.com/SuperMarioBean/38a5255fc1b14fb74739

thank you for this!