Home > rc-js-util > mapFirstKey
Gets the first inserted key in a Map.
Signature:
export declare function mapFirstKey<K, V>(map: Map<K, V>): K | undefined;
| Parameter | Type | Description | 
|---|---|---|
| map | Map<K, V> | 
Returns:
K | undefined
The first key in map, otherwise undefined where size 0.
See mapFirstKey().