JavaScript: Symbol.prototype

New in JS2015.

Symbol.prototype is the value of the property key "prototype" of the function Symbol. [see Symbol Object]

console.log(Symbol.hasOwnProperty("prototype"));

Type

Type of Symbol.prototype is Object .

console.log(typeof Symbol.prototype === "object");

Parent

Parent of Symbol.prototype is Object.prototype .

// parent of Symbol.prototype
console.log(Reflect.getPrototypeOf(Symbol.prototype) === Object.prototype);

Purpose

Symbol.prototype is the parent of all symbol objects.

let ss = Symbol();

console.log(
  Reflect.getPrototypeOf(Object(ss)) === Symbol.prototype,
);

// Object(ss) converts symbol primitive ss to a symbol object

[see Prototype and Inheritance]

Properties

• constructor
• description
• toString
• valueOf
• [ Symbol.toPrimitive ]
• [ Symbol.toStringTag ]

2017-02-10 following is work in progress.

Symbol.prototype.constructor

Symbol.prototype.constructor

The value is the object Symbol.

console.log(Symbol.prototype.constructor === Symbol);

Symbol.prototype.description

Return the description of the symbol.

Symbol.prototype.toString( )

return a string of the form:

"Symbol(description)"

const x = Symbol("xyz");
console.log(x.toString() === "Symbol(xyz)");

Symbol.prototype.valueOf ( )

Symbol.prototype [ Symbol.toPrimitive ] ( hint )

Symbol.prototype [ Symbol.toStringTag ]