Will be used to instantiate the internal Map.
Optional
iterable: Iterable<readonly [TKey, TVal | ReadonlySet<TVal>]>Entries to add to the map.
Readonly
[toPrivate
countPrivate
Readonly
mapAdds the given key/value binding to the Map.
Loops over all key/value bindings.
Optional
thisArg: any
A SetMultiMap that uses an internal Map based on the provided constructor.
In case no input constructor is provided, the default Map implementation will be used.
It is required that the value type of this map is not Set or any extension of Set, otherwise the
set
andadd
functions wil break.