Replace with regular expression

gistfile1.swift

import Foundation

struct Regex {
    let pattern: String
    let options: NSRegularExpressionOptions!
    
    private var matcher: NSRegularExpression {
        return NSRegularExpression(pattern: self.pattern, options: self.options, error: nil)!
    }
    
    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
    }
    
    func replace(string: String, withString: String) -> String {
        return string.stringByReplacingOccurrencesOfString(self.pattern, withString: withString, options: NSStringCompareOptions.RegularExpressionSearch, range: nil)
    }
}

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

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

func ~=<T: RegularExpressionMatchable>(pattern: Regex, matchable: T) -> Bool {
    return matchable.match(pattern)
}