[Home](./index.md) > [@apextoaster/js-utils](./js-utils.md) > [getHeadOrDefault](./js-utils.getheadordefault.md) ## getHeadOrDefault() function Get the first element from the specified key, within a map of lists, or a default value when the key does not exist or is nil. Signature: ```typescript export declare function getHeadOrDefault(map: Map>>, key: TKey, defaultValue: TVal): TVal; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | map | Map<TKey, ReadonlyArray<[Maybe](./js-utils.maybe.md)<TVal>>> | | | key | TKey | | | defaultValue | TVal | | Returns: TVal