Core API

Key behavior

• The constructor may register one initial callback.
• __invoke() and defer() both add callbacks to the stack.
• count() and isEmpty() inspect the current stack.
• Cleanup runs during destruction; there is no public flush() method.
• setErrorReporter() changes the global reporter used by all instances.

Common usage

use FastForward\Defer\Defer;

$defer = new Defer();
$defer(fn(): int => print "cleanup\n");

Public members

• __invoke(callable $callback, mixed ...$arguments): void
• defer(callable $callback, mixed ...$arguments): void
• isEmpty(): bool
• Countable::count(): int

Use the interface when your code only needs to register callbacks and should not depend on the concrete class.

defer()

Returns a new DeferInterface implementation.

scope()

Creates a temporary scope, passes it into your callback, and destroys it when the callback finishes.

using()

Creates a temporary scope, asks a factory callback to build a resource, then passes that resource into a second callback before cleanup runs.