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resolveList() function

Resolve entries of an array into a new array with the same indexes. If one or more entries of the source array are resolved to a promise by the resolver function, this method returns a promise which will be resolved to the new array with fully resolved entries.

Signature:

export declare function resolveList<T, V>(list: T[], resolver: (val: T, index: number, list: T[]) => ValueOrPromise<V>): ValueOrPromise<V[]>;

Parameters

Parameter Type Description
list T[] The original array containing the source entries
resolver (val: T, index: number, list: T[]) => ValueOrPromise<V> A function resolves an entry to a value or promise. It will be invoked with the property value, the property index, and the source array.

Returns:

ValueOrPromise<V[]>

Example

  • Example 1: resolve all entries synchronously
const result = resolveList(['a', 'b'], v => v.toUpperCase());

The result will be ['A', 'B'].

  • Example 2: resolve one or more entries asynchronously
const result = resolveList(['a', 'b'], v =>
  Promise.resolve(v.toUpperCase()),
);

The result will be a promise of ['A', 'B'].