TaskGroup::__construct

(PHP 8.6+, True Async 1.0)

public TaskGroup::__construct(?int $concurrency = null, ?Async\Scope $scope = null)

Creates a new task group.

Parameters

concurrency

Maximum number of concurrently running coroutines. null — no limit, all tasks are started immediately. When the limit is reached, new tasks are placed in a queue and started automatically when a slot becomes available.

scope

Parent scope. TaskGroup creates a child scope for its coroutines. null — the current scope is inherited.

Examples

Example #1 Without limits

<?php

use Async\TaskGroup;

$group = new TaskGroup();
$group->spawn(fn() => "task 1"); // starts immediately
$group->spawn(fn() => "task 2"); // starts immediately
$group->spawn(fn() => "task 3"); // starts immediately

Example #2 With concurrency limit

<?php

use Async\TaskGroup;

$group = new TaskGroup(concurrency: 2);
$group->spawn(fn() => "task 1"); // starts immediately
$group->spawn(fn() => "task 2"); // starts immediately
$group->spawn(fn() => "task 3"); // waits in queue

See Also

• TaskGroup::spawn — Add a task
• Scope — Coroutine lifecycle management