23 lines
686 B
Markdown
23 lines
686 B
Markdown
### bind
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Creates a function that invokes `fn` with a given context, optionally adding any additional supplied parameters to the beginning of the arguments.
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Return a `function` that uses `Function.apply()` to apply the given `context` to `fn`.
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Use `Array.concat()` to prepend any additional supplied parameters to the arguments.
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```js
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const bind = (fn, context, ...args) =>
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function() {
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return fn.apply(context, args.concat(...arguments));
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};
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```
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```js
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function greet(greeting, punctuation) {
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return greeting + ' ' + this.user + punctuation;
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}
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const freddy = { user: 'fred' };
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const freddyBound = bind(greet, freddy);
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console.log(freddyBound('hi', '!')); // 'hi fred!'
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```
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