call
Function
.prototype
.myCall = function (context
, ...args
) {
const fn
= Symbol('fn')
context
[fn
] = this
const res
= context
[fn
](...args
)
delete context
[fn
]
return res
}
apply
apply和call的差别，仅在于参数。
Function
.prototype
.myApply = function (context
, args
) {
const fn
= Symbol('fn')
context
[fn
] = this
const res
= context
[fn
](...args
)
delete context
[fn
]
return res
}
bind
Function
.prototype
.myBind = function (context
, ...args
) {
const self
= this
return function () {
return self
.apply(context
, args
)
}
}
