8ee50178f3
Correct: `Array.from()` (it’s a static method) Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method) This patch uses the common `#` syntax to denote `.prototype.`.
18 lines
400 B
Markdown
18 lines
400 B
Markdown
### nthArg
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Creates a function that gets the argument at index `n`. If `n` is negative, the nth argument from the end is returned.
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Use `Array.prototype.slice()` to get the desired argument at index `n`.
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```js
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const nthArg = n => (...args) => args.slice(n)[0];
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```
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```js
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const third = nthArg(2);
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third(1, 2, 3); // 3
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third(1, 2); // undefined
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const last = nthArg(-1);
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last(1, 2, 3, 4, 5); // 5
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```
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