The division operator `/`.

The get() method of WeakMap instances returns the value corresponding to the key in this WeakMap, or undefined if there is none. Object values are returned as the same reference that was originally stored, not as a copy, so mutations to the returned object will be reflected anywhere that reference is held, including inside the WeakMap.

The Reflect.getOwnPropertyDescriptor() static method is like Object.getOwnPropertyDescriptor(). It returns a property descriptor of the given property if it exists on the object, undefined otherwise.

The has() method of WeakMap instances returns a boolean indicating whether an entry with the specified key exists in this WeakMap or not.

The Object.defineProperty() static method defines a new property directly on an object, or modifies an existing property on an object, and returns the object.

The getOrInsert() method of WeakMap instances returns the value corresponding to the specified key in this WeakMap. If the key is not present, it inserts a new entry with the key and a given default value, and returns the inserted value.

The forEach() method of Map instances executes a provided function once per each key/value pair in this map, in insertion order.

The getOrInsertComputed() method of WeakMap instances returns the value corresponding to the specified key in this WeakMap. If the key is not present, it inserts a new entry with the key and a default value computed from a given callback, and returns the inserted value.

The unary negation operator `-`.

An iterator over subslices separated by elements that match a predicate function, limited to a given number of splits, starting from the end of the slice.