# PSR Clock
This repository holds the interface for [PSR-20][psr-url].
Note that this is not a clock of its own. It is merely an interface that
describes a clock. See the specification for more details.
## Installation
```bash
composer require psr/clock
```
## Usage
If you need a clock, you can use the interface like this:
```php
<?php
use Psr\Clock\ClockInterface;
class Foo
{
private ClockInterface $clock;
public function __construct(ClockInterface $clock)
{
$this->clock = $clock;
}
public function doSomething()
{
/** @var DateTimeImmutable $currentDateAndTime */
$currentDateAndTime = $this->clock->now();
// do something useful with that information
}
}
```
You can then pick one of the [implementations][implementation-url] of the interface to get a clock.
If you want to implement the interface, you can require this package and
implement `Psr\Clock\ClockInterface` in your code.
Don't forget to add `psr/clock-implementation` to your `composer.json`s `provides`-section like this:
```json
{
"provides": {
"psr/clock-implementation": "1.0"
}
}
```
And please read the [specification text][specification-url] for details on the interface.
[psr-url]: https://www.php-fig.org/psr/psr-20
[package-url]: https://packagist.org/packages/psr/clock
[implementation-url]: https://packagist.org/providers/psr/clock-implementation
[specification-url]: https://github.com/php-fig/fig-standards/blob/master/proposed/clock.md