Boolean.prototype

The Boolean.prototype property represents the prototype for the Boolean constructor.

Description

Boolean instances inherit from Boolean.prototype. You can use the constructor's prototype object to add properties or methods to all Boolean instances.

Properties

Boolean.prototype.constructor

Returns the function that created an instance's prototype. This is the Boolean function by default.

Methods

Boolean.prototype.toSource()

Returns a string containing the source of the Boolean object; you can use this string to create an equivalent object. Overrides the Object.prototype.toSource() method.

Boolean.prototype.toString()

Returns a string of either "true" or "false" depending upon the value of the object. Overrides the Object.prototype.toString() method.

Boolean.prototype.valueOf()

Returns the primitive value of the Boolean object. Overrides the Object.prototype.valueOf() method.

Specifications

Specification	Status	Comment
ECMAScript 1st Edition (ECMA-262)	Standard	Initial definition. Implemented in JavaScript 1.0.
ECMAScript 5.1 (ECMA-262) The definition of 'Boolean.prototype' in that specification.	Standard
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Boolean.prototype' in that specification.	Standard
ECMAScript 2017 Draft (ECMA-262) The definition of 'Boolean.prototype' in that specification.	Draft

Browser compatibility