TypeError: fn.bind is not a function"

vue.esm.js?efeb:205 Uncaught TypeError: fn.bind is not a function
at nativeBind (vue.esm.js?efeb:205)
at initMethods (vue.esm.js?efeb:3541)
at initState (vue.esm.js?efeb:3309)
at VueComponent.Vue._init (vue.esm.js?efeb:4628)
at new VueComponent (vue.esm.js?efeb:4798)
at createComponentInstanceForVnode (vue.esm.js?efeb:4310)
at init (vue.esm.js?efeb:4131)
at createComponent (vue.esm.js?efeb:5608)
at createElm (vue.esm.js?efeb:5555)
at VueComponent.patch [as __patch__] (vue.esm.js?efeb:6091)

这是因为在methods中定义的可能是一个对象，或者是定义的方法名与某个对象名称冲突了，所以在fn.bind的时候，是绑定的对象，而不是方法，拿到的值未undefined