RawRepresentable+AllValues.swift

extension RawRepresentable where RawValue: Numeric {
    /// Returns all the values of a RawRepresentable whose RawValue is Numeric. This static property expressly exists
    /// for enumerations, though can be used elsewhere. Works only for contiguous values.
    /// Supposing we have:
    /// ```
    /// enum Counter {
    ///     case one, two
    /// }
    /// ```
    /// then `Counter.allValues == [.one, .two]`.
    static var allValues: [Self] {
        var i: RawValue = 0
        return Array(AnyIterator {
            let result = self.init(rawValue: i)
            i += 1
            
            return result
        })
    }
}