Hands-On Data Structures and Algorithms with JavaScript

API differences

The API for Map and WeakMap is very similar when it comes to standard operations, such as set() and get(). This makes the API very straightforward and contains the following:

• Map.prototype.size: Returns the size of the map; not available on typical objects unless you loop and count
• Map.prototype.set: Sets a value for a given key and returns the entire new map
• Map.prototype.get: Gets a value for a given key and returns undefined if not found
• Map.prototype.delete: Deletes a value for a given key and returns true if deletion was successful, otherwise false
• Map.prototype.has: Checks the map for the presence of an element with the key provided; returns boolean
• Map.prototype.clear: Clears the map; returns nothing
• Map.prototype.forEach ...