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mapInitializeGet() function

Gets the value from a Map for a given key, where the value is undefined or hasn’t been set, the callback’s return will be inserted into the Map and returned.

Signature:

export declare function mapInitializeGet<TMapKey, TKey extends TMapKey, TMapValue, TValue extends TMapValue>(map: Map<TMapKey, TMapValue>, key: TKey, getValue: (key: TKey) => TValue): TMapValue;

Parameters

Parameter Type Description
map Map<TMapKey, TMapValue> The Map to search and modify.
key TKey The key to search for / set in map.
getValue (key: TKey) => TValue The function to call if a value is not found.

Returns:

TMapValue

The value in map, otherwise the result of the getValue.

Remarks

See mapInitializeGet().