[Home](./index.md) > [rc-js-util](./rc-js-util.md) > [DirtyCheckedUniqueCollection](./rc-js-util.dirtycheckeduniquecollection.md) > [(constructor)](./rc-js-util.dirtycheckeduniquecollection._constructor_.md) ## DirtyCheckedUniqueCollection.(constructor) Constructs a new instance of the `DirtyCheckedUniqueCollection` class **Signature:** ```typescript constructor(itemsToCopy?: readonly TItem[] | ReadonlySet); ``` ## Parameters

Parameter	Type	Description
itemsToCopy	readonly TItem\[\] \| ReadonlySet<TItem>	_(Optional)_