tom-weatherhead/common-utilities.ts

// github:tom-weatherhead/common-utilities.ts/src/asynchronous.ts

// From https://codeburst.io/javascript-async-await-with-foreach-b6ba62bbf404 :

// const waitFor = ms => new Promise(r => setTimeout(r, ms));

export async function asyncForEach<T>(
    array: T[],
    callback: (element: T, index: number, array: T[]) => unknown
): Promise<void> {
    for (let index = 0; index < array.length; index++) {
        await callback(array[index], index, array);
    }
}

/*
asyncForEach([1, 2, 3], async (num) => {
    await waitFor(50);
    console.log(num);
});

console.log('Done');
*/

export async function asyncMap<T, U>(
    array: T[],
    callback: (element: T, index: number, array: T[]) => U
): Promise<U[]> {
    const result: U[] = [];

    for (let index = 0; index < array.length; index++) {
        result.push(await callback(array[index], index, array));
    }

    return result;
}

export function delayAndResolve(ms: number): Promise<void> {
    return new Promise<void>(
        (
            resolve: (value?: void) => void,
            /* eslint-disable-next-line @typescript-eslint/no-unused-vars */
            reject: (reason?: unknown) => void
        ): void => {
            setTimeout(() => {
                resolve();
            }, ms);
        }
    );
}

export function delayAndResolveWithValue<T>(ms: number, t: T): Promise<T> {
    return new Promise<T>(
        (
            resolve: (value: T | PromiseLike<T>) => void,
            /* eslint-disable-next-line @typescript-eslint/no-unused-vars */
            reject: (reason?: unknown) => void
        ): void => {
            setTimeout(() => {
                resolve(t);
            }, ms);
        }
    );
}

export async function sleep(ms: number): Promise<void> {
    // ms is the number of milliseconds for which to sleep.

    await new Promise((r) => setTimeout(r, ms));
}