Function hasHandler

tools/pythonauto/static/codemirrorepl/codemirror.js:6880–6883

(emitter, type)

  }

  function hasHandler(emitter, type) {
    var arr = emitter._handlers && emitter._handlers[type];
    return arr && arr.length > 0;
  }

  // Add on and off methods to a constructor's prototype, to make
  // registering events on such objects more convenient.