rc-js-util
Version:
A collection of TS and C++ utilities to help writing performant and correct applications, achieved through strict typing and (removable) invariant checking.
35 lines (34 loc) • 1.04 kB
text/typescript
/**
* @public
* Used with maps that store arrays. Where an array exists for a given key the values will be appended to that array, otherwise a copy of values array will be inserted.
* @param map - The `Map` to check. May be modified.
* @param key - The key to lookup in `map`.
* @param values - The values to concat.
*
* @remarks
* See {@link (mapConcat: 1)}.
*/
export function mapConcat<TKey, TValue>(map: Map<TKey, TValue[]>, key: TKey, values: readonly TValue[]): void;
/**
* @public
* {@inheritDoc (mapConcat: 1)}
*/
export function mapConcat<TKey extends object, TValue>(map: WeakMap<TKey, TValue[]>, key: TKey, values: readonly TValue[]): void;
export function mapConcat<TKey extends object, TValue>
(
map: Map<TKey, TValue[]> | WeakMap<TKey, TValue[]>,
key: TKey,
valuesToConcat: readonly TValue[],
)
: void
{
const values = map.get(key);
if (values != null)
{
map.set(key, values.concat(valuesToConcat));
}
else
{
map.set(key, valuesToConcat.slice());
}
}