Practice: Working with Map Objects

Instance properties

These properties are defined on Map.prototype and shared by all Map instances.

Map.prototype.constructor

The constructor function that created the instance object. For Map instances, the initial value is the Map constructor.

Map.prototype.size

Returns the number of key/value pairs in the Map object.

Map.prototype[@@toStringTag]

The initial value of the @@toStringTag property is the string "Map". This property is used in Object.prototype.toString().