reduce

Reduces values to a single value.

iterable.reduce(x, fn, [ths]);
// x:   an iterable
// fn:  reduce function (acc, v, i, x)
// acc: initial value

const iterable = require('extra-iterable');

var x = [1, 2, 3, 4];
[...iterable.reduce(x, (acc, v) => acc+v)];
// 10

[...iterable.reduce(x, (acc, v) => acc+v, 100)];
// 110

references

• Array.prototype.reduce(): MDN web docs
• iterable_reduce: PHP
• Data.List.reduce(): Haskell