Error+legibleDescription.swift

public extension Error {
    var legibleDescription: String {
        if let error = self as? LocalizedError, let description = error.errorDescription {
            return description
        } else if (self as AnyObject).isKind(of: NSError.self) {
            return localizedDescription
        } else {
            let mirror = Mirror(reflecting: self)
            switch mirror.displayStyle {
            case .enum?:
                return "\(type(of: self)).\(self)"
            case .class?:
                return "\(self)"
            default:
                return String(describing: self)
            }
        }
    }
}