@extra-array/accumulate-update

Produces accumulating values. 🏃 📼 📦 🌔 📒

Alternatives: accumulate, accumulate$.
Similar: map, filter, reduce, accumulate.
This is part of package extra-array.

array.accumulate$(x, fn, [acc]);
// x:   an array (updated)
// fn:  reduce function (acc, v, i, x)
// acc: initial value
// --> x

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

var x = [1, 2, 3, 4];
array.accumulate$(x, (acc, v) => acc+v);
// [ 1, 3, 6, 10 ]

x;
// [ 1, 3, 6, 10 ]

var x = [1, 2, 3, 4];
array.accumulate$(x, (acc, v) => acc+v, 100);
// [ 101, 103, 106, 110 ]

references

• Data.List.scanl: Haskell
• itertools.accumulate: Python