type

WeakMap

src @Js class WeakMap : Obj

WeakMap is a collection of key/value pairs in which the keys are weakly referenced. The keys must be objects and the values can be arbitrary values.

delete	Removes any value associated to the key.
get	Returns the value associated to the key, or `null` if there is none.
has	Return `true` if key exists in this map.
set	Sets value for given key in this map.

src Bool delete(Obj key)

Removes any value associated to the key. Returns true if an element has been removed successfully.

Returns the value associated to the key, or null if there is none.

src Bool has(Obj key)

Return true if key exists in this map.

Sets value for given key in this map. Returns this.