takeWhile

Extracts values from left, while a test passes. 🏃 📼 📦 🌔 📒

Alternatives: take, takeRight, takeWhile, takeWhileRight.
Similar: take, drop.

iterable.takeWhile(x, fn);
// x:  an iterable
// fn: test function (v, i, x)

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

var x = [1, 2, 3, 4, 5];
[...iterable.takeWhile(x, v => v < 3)];
// [ 1, 2 ]

[...iterable.takeWhile(x, v => v < 4)];
// [ 1, 2, 3 ]

references

• Data.List.takeWhile: Haskell
• Array.prototype.slice: MDN web docs