> For the complete documentation index, see [llms.txt](https://quantumphp.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://quantumphp.gitbook.io/docs/packages/hook/helpers.md).

# Helpers

The package exposes one helper function.

## `hook()`

```php
function hook(): HookManager
```

Behavior:

1. checks whether `HookManager::class` is registered in DI
2. registers it if missing
3. returns `Di::get(HookManager::class)`

That means repeated `hook()` calls reuse the same `HookManager` instance for the current DI container.

## Practical effect of the shared instance

Because the helper resolves one shared manager:

* listeners added through `hook()->on(...)` stay on that shared instance until they are fired
* firing a hook through one call site affects listeners attached from other call sites using the same container
* constructor-time hook registration runs only when the shared manager is first created

## Failure cases

The helper itself does not catch errors.

It can surface:

* DI registration or resolution failures
* constructor failures from `HookManager`, including missing or invalid hook configuration


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