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30-seconds-of-code/snippets/bindKey.md
Angelos Chalaris c03ff71088 Update bindKey.md
2018-08-10 10:47:56 +03:00

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### bindKey
Creates a function that invokes the method at a given key of an object, optionally adding any additional supplied parameters to the beginning of the arguments.
Return a `function` that uses `Function.apply()` to bind `context[fn]` to `context`.
Use the spread operator (`...`) to prepend any additional supplied parameters to the arguments.
```js
const bindKey = (context, fn, ...boundArgs) => (...args) => context[fn].apply(context, [...boundArgs, ...args]);
```
```js
const freddy = {
user: 'fred',
greet: function(greeting, punctuation) {
return greeting + ' ' + this.user + punctuation;
}
};
const freddyBound = bindKey(freddy, 'greet');
console.log(freddyBound('hi', '!')); // 'hi fred!'
```