Function createDelayedPLimit

  • createDelayedPLimit(concurrency?, delayMs?): (<T>(fn: (() => Promise<T>)) => Promise<T>)

  • Creates a concurrency-limited queue with a fixed delay between the start times of tasks.

    Parameters

    • concurrency: number = 1

      How many tasks can run simultaneously

    • delayMs: number = 100

      Milliseconds to wait after one task starts before the next starts

    Returns (<T>(fn: (() => Promise<T>)) => Promise<T>)

    A function that accepts a task (a function returning a Promise) and returns a Promise of its result.

    Example usage:

    const limit = createDelayedPLimit(2, 100); // concurrency=2, delay=100ms

    async function doAsync(label: string) {
      console.log(`Starting: ${label}`);
      await new Promise((r) => setTimeout(r, 500));
      console.log(`Finished: ${label}`);
      return label;
    }

    // Queue some tasks
    const tasks = ['A', 'B', 'C', 'D'].map(
      (label) => limit(() => doAsync(label)),
    );

    // Wait for all
    const results = await Promise.all(tasks);
    console.log(results); // ['A', 'B', 'C', 'D']
      • <T>(fn): Promise<T>

      • The function returned by createDelayedPLimit. It schedules a new task (fn) under concurrency + delay constraints, returning a Promise of fn()'s result.

        Type Parameters

        • T

        Parameters

        • fn: (() => Promise<T>)
            • (): Promise<T>

            • Returns Promise<T>

        Returns Promise<T>

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