Typed class properties have been added in PHP 7.4 and provide a major improvement to PHP&#39;s type system. These changes are fully opt-in and backwards compatible. Here&#39;s a very short summary of how typed properties work:
<ul>
<li>They are available as of PHP 7.4, which is scheduled to be released in November of 2019</li>
<li>They are only available in classes and require an access modifier: <code>public</code>, <code>protected</code> or <code>private</code>; or <code>var</code>.</li>
<li>All types are allowed, except <code>void</code> and <code>callable</code></li>
</ul>
This is what they look like in action:
<pre><code>class Foo
{
 public int $a;

 public ?string $b = 1;

 private Foo $prop;

 protected static string $static = 'default';
}
</code></pre>There&#39;s lots more to tell about typed properties, so I wrote an in-depth post about them here: <a target='_blank' rel='noopener noreferrer' href="https://stitcher.io/blog/typed-properties-in-php-74">https://stitcher.io/blog/typed-properties-in-php-74</a>.

Typed class properties have been added in PHP 7.4 and provide a major improvement to PHP's type system. These changes are fully opt-in and backwards compatible. Here's a very short summary of how typed properties work:

- They are available as of PHP 7.4, which is scheduled to be released in November of 2019
- They are only available in classes and require an access modifier: `public`, `protected` or `private`; or `var`.
- All types are allowed, except `void` and `callable`

This is what they look like in action:

```
class Foo
{
    public int $a;

    public ?string $b = 1;

    private Foo $prop;

    protected static string $static = 'default';
}
```

There's lots more to tell about typed properties, so I wrote an in-depth post about them here: [https://stitcher.io/blog/typed-properties-in-php-74](https://stitcher.io/blog/typed-properties-in-php-74).

Typed properties in PHP 7.4