Array API: array.fill()

Array.prototype.fill can fill up an array with one value

fill(0) will populate 0 into each array element

const arr = new Array(3).fill(); assert.deepEqual(arr, [0, 0, 0]);

fill only changes content, adds no new elements

const arr = [undefined].fill(0); assert.deepEqual(arr, []);

second parameter to fill() is the position where to start filling

const fillPosition = 0; const arr = [1,2,3].fill(42, fillPosition); assert.deepEqual(arr, [1, 2, 42]);

third parameter is the position where filling stops

const fillStartAt = 1; const fillEndAt = 1; const arr = [1,2,3].fill(42, fillStartAt, fillEndAt); assert.deepEqual(arr, [1, 42, 3]);

Links

discussion A discussion in a github issue, about how to use this kata.
mdn docs API doc on MDN.

Required Knowledge

• `const` declaration (Block scope)

Related Katas

Array API

• array.sort() basics
• array.sort() can take a compare function
• array.shift() (as introduced in ES3)
• array.push() (as introduced in ES3)
• Array.from()
• Array.of()
• array.fill()
• array.find()
• array.findIndex()
• array.entries()
• array.keys()
• array.values()
• array.includes()
• array.toReversed()

Difficulty Level

TBD

First Published

28 April 2015

Stats

4 tests to solve