demo/bundle.js
// save current target element in closure
save current target element in closure
save current target element in closure
function onceHandler () {
                var res = handler.apply(null, arguments);
                if (res !== null) {
                  remove$2(event, onceHandler, capture, _target);
                }
              }
function onceHandler ( ) { var res = handler . apply ( null , arguments ) ; if ( res !== null ) { remove$2 ( event , onceHandler , capture , _target ) ; } }
save current target element in closure
save current target element in closure