RegexTester

A simple Mac app for making Swift regex patterns.

Regex is displayed in a "normal" text field, above, so that you can edit it easily, and below it is an "escaped" text field. These fields mirror each other as you go.

The opts button allows you to toggle all the options in the NSRegularExpression.Options option set, and copy produces:

let regexStr = "commit ([0-9a-f]{40}).*?(Merge: [0-9a-f ]{15}\\n)?\\nAuthor: (.*?)\\nDate:   (.*?)\\n(.*?\\n\\n)"
let regex = try? NSRegularExpression(pattern: regexStr, options: [.dotMatchesLineSeparators])

which you can paste into your code and mod at will.*

Attribution

Written by Steve Sparks (@barbecuesteve), engineer at Big Nerd Ranch. Screenshot shows a portion of the git log of BNR's Deferred library.

Known Issues

Some expressions can cause the beachball of death due to catastrophic backtracking. No attempt is taken to limit the greediness of your expression. You've been warned. Kill it and restart it.

Contributing

Please do! Open a pull request.

--

*Personally I do it this way. It is more maintainable.

extension NSRegularExpression {

    enum Regex: String {
        case gitLogEntry = "commit ([0-9a-f]{40}).*?(Merge: [0-9a-f ]{15}\n)?\nAuthor: (.*?)\nDate: (.*?)\n\n(.*?)\n\n"
    }

    convenience init(regex: Regex, options: NSRegularExpression.Options) throws {
        try self.init(pattern: regex.rawValue, options: options)
    }
}

let myRegex = try NSRegularExpression(regex: .gitLogEntry, options: [.dotMatchesLineSeparators])