The answer
Return a new function that calls the original with call: Function.prototype.myBind = function(context, ...presetArgs) { return (...args) => this.call(context, ...presetArgs, ...args); }.
call, apply, and bind: Interview Preparation Guide
How do you implement a polyfill for bind in an interview?
More FAQs in call, apply, and bind: Interview Preparation Guide
What each does (call: immediate comma args, apply: immediate array args, bind: returns function), how to implement polyfills, use cases (method borrowing, fixing this, partial application), precedence (new > bind > call > implicit > default), arrows ignore them, and re-binding is not possible.
Predict the output of code using call/apply/bind with a specific this and arguments. For example: foo.call(obj, 1, 2) where foo returns this.x + a + b and obj.x is 10. Answer: 13.
new (highest) > bind > call/apply > implicit (method call) > default (plain call). Arrow functions are an exception: they use lexical this and ignore all of these rules.
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