Ruby, Underscoreライクなtapメソッドのextension実装

NSObject+tap.swift

import UIKit

protocol Tappable : class {
}

extension Tappable where Self : NSObject {
    
    func tap(@noescape function: (Self) -> ()) -> Self {
        function(self)
        return self
    }
}

extension NSObject : Tappable {}
extension UIView : Tappable {}

#if debug
func tap_example() {
    UIView().tap { (a : UIView) in
        print("\(a)")
    }
    
    UIStackView().tap { (a : UIStackView) in
        print("\(a)")
    }

    let _ = UILabel().tap {
        $0.text = "ほげほげ"
    }
    
    NSObject().tap { (a : NSObject) in
        print("\(a)")
    }
}
#endif