assertSetItem()function

assertSetItem(set: ImmutableSet<T>, item: unknown, caller: AnyCaller = assertSetItem): asserts item is T

Param	Type
`set`	`ImmutableSet<T>`	The set to look in. required
`item`	`unknown`	The value to assert membership of. required
`caller`	`AnyCaller`	Function to attribute a thrown error to (defaults to `assertSetItem`). Defaults to `assertSetItem`

Return
`asserts item is T`

Throws
`RequiredError`	If `item` does not exist in `set`.

Assert that an unknown value is an item in a set.

Examples

assertSetItem(new Set(["a"]), "a"); // Passes.