RegExp.prototype.multiline

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The multiline accessor property of RegExp instances returns whether or not the m flag is used with this regular expression.

Try it

const regex1 = /^football/;
const regex2 = /^football/m;

console.log(regex1.multiline);
// Expected output: false

console.log(regex2.multiline);
// Expected output: true

console.log(regex1.test("rugby\nfootball"));
// Expected output: false

console.log(regex2.test("rugby\nfootball"));
// Expected output: true

RegExp.prototype.multiline has the value true if the m flag was used; otherwise, false. The m flag indicates that a multiline input string should be treated as multiple lines. For example, if m is used, ^ and $ change from matching at only the start or end of the entire string to the start or end of any line within the string.

The set accessor of multiline is undefined. You cannot change this property directly.

Examples

Using multiline

js
const regex = /^foo/m;

console.log(regex.multiline); // true

Specifications

Specification

ECMAScript® 2027 Language Specification
# sec-get-regexp.prototype.multiline

Browser compatibility

Enable JavaScript to view this browser compatibility table.

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Standard built-in objects
RegExp
Constructor
1. RegExp()
Static methods
1. escape()
Static properties
Instance methods
Instance properties
Inheritance
Object/Function
Static methods
Static properties
Instance methods
Instance properties
1. __proto__
2. constructor