30-seconds-of-code/snippets/reduceSuccessive.md

title, tags

title	tags
reduceSuccessive	array,function,intermediate

Applies a function against an accumulator and each element in the array (from left to right), returning an array of successively reduced values.

• Use Array.prototype.reduce() to apply the given function to the given array, storing each new result.

const reduceSuccessive = (arr, fn, acc) =>
  arr.reduce((res, val, i, arr) => (res.push(fn(res.slice(-1)[0], val, i, arr)), res), [acc]);

reduceSuccessive([1, 2, 3, 4, 5, 6], (acc, val) => acc + val, 0); // [0, 1, 3, 6, 10, 15, 21]