Empty an array

Remove every item in place, so all references see an empty array.

JavaScriptNode.js & browsers Version 1.0.0 · MIT · .md

function empty(values) { values.length = 0; return values; }

Usage

const queue = ['ana@example.com', 'rui@example.com'];
const sameQueue = queue;
empty(queue);
sameQueue.length; // → 0
let list = [1, 2];
const alias = list;
list = [];
alias; // → [1, 2]

Lines marked → were executed in Node.js 22 and in headless Chromium, and each result was compared with the value shown. Lines marked e.g. are illustrative.

Know the limits

• Setting length mutates the array. Assigning [] only rebinds one variable, as the second example shows.
• The original returned 0, the assigned length; this version returns the array.

The function above is the code the usage lines run. It does not validate its arguments; add checks where it receives untrusted input.

Keep exploring

• Clone an array — Create a new array without copying the objects inside it.
• Remove duplicate values — Keep the first occurrence of each value, in its original order.
• Flatten a nested array — Turn a nested array into one sequence of values.