Vue.directive('tap',{
    bind(el, binding, vNode){
        let expression = binding.value;
        let handler    = expression.name;
        let args       = expression.args

        on(el, 'touchstart', (e)=>{
            
            let startX = e.changedTouches[0].clientX;
            let startY 
 
= e.changedTouches[0].clientY;

            once(el, 'touchend',(ev)=>{

                let disX = Math.abs(ev.changedTouches[0].clientX-startX);
                let disY = Math.abs(ev.changedTouches[0].clientY-startY);

                if(disX == 0 && disY ==0){
                    handler(args);
                }
            })
        })
    }
})