### Initialize Watchman Watcher

Source: https://github.com/phpactor/amp-fswatch/blob/master/README.md

Shows how to instantiate the WatchmanWatcher for file system monitoring. This watcher requires Watchman to be installed on the system and works across Linux, Mac, and Windows.

```PHP
use Phpactor\AmpFsWatch\Watcher\Watchman\WatchmanWatcher;

$watcher = new WatchmanWatcher($config, $logger);
```

--------------------------------

### Monitor File System Changes with Amp FS Watch

Source: https://github.com/phpactor/amp-fswatch/blob/master/README.md

Demonstrates a comprehensive setup for monitoring file system changes using Amp FS Watch. It initializes a PSR logger, configures a WatcherConfig for a given path, and sets up a PatternMatchingWatcher that wraps a FallbackWatcher. The FallbackWatcher includes BufferedWatcher, InotifyWatcher, FindWatcher, PhpPollWatcher, and FsWatchWatcher. The example then yields the watcher process and continuously prints file change notifications.

```PHP
Loop::run(function () use () {

    $logger = // create a PSR logger
    $config = new WatcherConfig([$path]);
    $watcher = new PatternMatchingWatcher(
        new FallbackWatcher([
            new BufferedWatcher(new InotifyWatcher($config, $logger), 10),
            new FindWatcher($config, $logger),
            new PhpPollWatcher($config, $logger),
            new FsWatchWatcher($config, $logger)
        ], $logger),
        [ '/**/*.php' ],
        []
    );

    $process = yield $watcher->watch([$path]);

    while (null !== $file = yield $process->wait()) {
        fwrite(STDOUT, sprintf('[%s] %s (%s)' . "\n", date('Y-m-d H:i:s.u'), $file->path(), $file->type()));
    }
});
```

--------------------------------

### PHP File Watcher: Proposed Promise-Based API

Source: https://github.com/phpactor/amp-fswatch/blob/master/adr/0001-use-callback.md

This example illustrates a proposed promise-based API for file watching. It involves monitoring paths and then yielding `wait()` on a stream to asynchronously retrieve `ModifiedFile` objects, addressing potential backlogs.

```php
$stream = $watcher->monitor($paths);
while (null !== $modifiedFile = yield $stream->wait()) {
    // do something
}
```

--------------------------------

### Initialize FsWatch Watcher

Source: https://github.com/phpactor/amp-fswatch/blob/master/README.md

Demonstrates how to use the FsWatchWatcher. This watcher is cross-platform and leverages native system capabilities when possible, though it is noted as unstable and not extensively tested.

```PHP
use Phpactor\AmpFsWatch\Watcher\FsWatch\FsWatchWatcher;

$watcher = new FsWatchWatcher($config, $logger);
// ...
```

--------------------------------

### Initialize Inotify Watcher

Source: https://github.com/phpactor/amp-fswatch/blob/master/README.md

Illustrates the creation of an InotifyWatcher instance. This watcher utilizes the Linux `inotifywait` binary for real-time file change detection, providing efficient monitoring on Linux systems.

```PHP
use Phpactor\AmpFsWatch\Watcher\Inotify\InotifyWatcher;

$watcher = new InotifyWatcher($config, $logger);
// ...
```

--------------------------------

### Initialize Fallback Watcher

Source: https://github.com/phpactor/amp-fswatch/blob/master/README.md

Illustrates the configuration of a FallbackWatcher. This watcher automatically selects the first supported watcher from a provided list based on the current system's capabilities, offering a robust solution for varying environments.

```PHP
use Phpactor\AmpFsWatch\Watcher\Fallback\FallbackWatcher;

$watcher = new FallbackWatcher(
    [
        new InotifyWatcher($logger),
        new FindWatcher(500, $logger)
    ],
    $logger
);
// ...
```

--------------------------------

### Initialize Find Watcher

Source: https://github.com/phpactor/amp-fswatch/blob/master/README.md

Shows the instantiation of a FindWatcher. This watcher polls for file changes using the `find` binary, typically on Linux and Mac systems. It's important to note potential compatibility issues with non-GNU/BSD `find` variants due to the use of the `-newerxy` switch.

```PHP
use Phpactor\AmpFsWatch\Watcher\Find\FindWatcher;

$watcher = new FindWatcher($config, $logger);
// ...
```

--------------------------------

### Initialize PHP Poll Watcher

Source: https://github.com/phpactor/amp-fswatch/blob/master/README.md

Explains how to set up the PhpPollWatcher. This is the most compatible option as it works on all environments, but it is also the slowest and most resource-intensive due to its pure PHP implementation.

```PHP
use Phpactor\AmpFsWatch\Watcher\Find\FindWatcher;

$watcher = new PhpPollWatcher($config, $logger);
// ...
```

--------------------------------

### PHP File Watcher: Proposed Emitter/Iterator API

Source: https://github.com/phpactor/amp-fswatch/blob/master/adr/0001-use-callback.md

This snippet presents another alternative API design using an emitter or iterator pattern. It shows how to iterate over modified files by yielding `advance()` and then retrieving the current `ModifiedFile`.

```php
$iterator = $watcher->watch($paths);

while (yield $iterator->advance()) {
    $modifiedFile = $iterator->getCurrent();
    // do something
}
```

--------------------------------

### PHP File Watcher: Callback-Based API Usage

Source: https://github.com/phpactor/amp-fswatch/blob/master/adr/0001-use-callback.md

This snippet demonstrates the existing public API for file watching. It shows how to register a callback function that is executed whenever a file is modified, receiving a `ModifiedFile` object as an argument.

```php
$watcher->monitor($paths, function (ModifiedFile $file) {
   // do something
});
```

--------------------------------

### PHP File Watcher with Promises (Improved)

Source: https://github.com/phpactor/amp-fswatch/blob/master/adr/0002-do-not-use-callback.md

Refactored implementation of the file watcher that yields promises for modified files. This approach uses `yield $watcher->wait()` to retrieve files, making it more suitable and easier to integrate into Amp projects.

```php
while (null !== $file = yield $watcher->wait())
    $job = $this->indexer->getJob($file->path());

    foreach ($job->generator() as $file) {
        yield new Delayed(1);
    }
});
```

--------------------------------

### PHP File Watcher with Callback (Deprecated)

Source: https://github.com/phpactor/amp-fswatch/blob/master/adr/0002-do-not-use-callback.md

Initial implementation of a file watcher using a callback function to handle modified files. This approach was deemed 'odd' and not properly integrated with co-routines, leading to a decision to refactor.

```php
$this->watcher->watch($this->paths, function (ModifiedFile $file) {
    asyncCall(function () use ($file) {
        $job = $this->indexer->getJob($file->path());

        foreach ($job->generator() as $file) {
            yield new Delayed(1);
        }
    });
});
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.