requireMapItem()function

requireMapItem(map: ImmutableMap<K, T>, key: K, caller: AnyCaller = requireMapItem): T

Param	Type
`map`	`ImmutableMap<K, T>`	The map to read from. required
`key`	`K`	The key to look up. required
`caller`	`AnyCaller`	Function used to attribute a thrown error to the calling site. Defaults to `requireMapItem`

Return
`T`	The value for `key`.

Throws
`RequiredError`	If `key` does not exist in `map`.

Get an item in a map, or throw RequiredError if it doesn't exist.

Examples

requireMapItem(new Map([["a", 1]]), "a") // 1