None.

A string representing the specified symbol value.

The Symbol object overrides the toString method of Object; it does not inherit Object.prototype.toString(). For Symbol values, the toString method returns a descriptive string in the form "Symbol(description)", where description is the symbol's description.

The toString() method requires its this value to be a Symbol primitive or wrapper object. It throws a TypeError for other this values without attempting to coerce them to symbol values.

Because Symbol has a [@@toPrimitive]() method, that method always takes priority over toString() when a Symbol object is coerced to a string. However, because Symbol.prototype[@@toPrimitive]() returns a symbol primitive, and symbol primitives throw a TypeError when implicitly converted to a string, the toString() method is never implicitly called by the language. To stringify a symbol, you must explicitly call its toString() method or use the String() function.

The only way to make JavaScript implicitly call toString() instead of [@@toPrimitive]() on a symbol wrapper object is by deleting the @@toPrimitive method first.

delete Symbol.prototype[Symbol.toPrimitive];
console.log(`${Object(Symbol("foo"))}`); // "Symbol(foo)"

• Object.prototype.toString()