16 lines
480 B
Markdown
16 lines
480 B
Markdown
### Compose functions
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Use the `...rest` operator to gather all function arguments into an array. Return a function which takes
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a single argument and uses `Array.reduceRight()` to return the result of applying each function.
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```js
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const compose = (...fns) => n => fns.reduceRight((acc, fn) => fn(acc), n);
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/*
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const addOne = n => n + 1;
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const square = n => n * n;
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const double = n => n * 2;
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compose(addOne, square, double)(2) -> 17
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equivalent to: addOne(square(double(2)))
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*/
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```
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