[Home](./index.md) > [rc-js-util](./rc-js-util.md) > [DirtyCheckedUniqueCollection](./rc-js-util.dirtycheckeduniquecollection.md) > [mapInitializeAdd](./rc-js-util.dirtycheckeduniquecollection.mapinitializeadd_1.md) ## DirtyCheckedUniqueCollection.mapInitializeAdd() method **Signature:** ```typescript static mapInitializeAdd(map: WeakMap>, key: TKey, value: TValue): boolean; ``` ## Parameters

Parameter	Type	Description
map	WeakMap<TKey, [IDirtyCheckedUniqueCollection](./rc-js-util.idirtycheckeduniquecollection.md)<TValue>>
key	TKey
value	TValue

**Returns:** boolean