New Features in PHP 7.4

Since the last year php community is working alot on bringing new features in PHP. So this year in PHP 7.4 is coming with alot of interesting features. Here’s a list of some features coming this year.

Arrow Functions

Arrow functions were first introduced in 2016. But due to some reasons the rfc was withdrawn. And now after two years it’s finally coming in PHP 7.4. They are also called as “short clousers” or one-liner functions.

Here’s the syntax

$numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
array_filter($numbers, fn(int $number): int => $number % 2 == 0);

Somethings to note about the syntax

They start with fn
There’s no return statement
There’s only one expression that is the default return
$this is available like a normal clousre
They can always access the parent scope, no need for the use keyword
Arguments and return types can be type hinted

Check the rfc for more detail.

Typed Properties

Finally after a long time this feature is accepted. Now we don’t have to use annotations anymore.

class Test { 
	public  string $x; 
	public  int	   $y;
	public  ?Foo   $foo; 
	protected  static  string $static = 'default';
}

For more detail check the rfc

Array spread operator

Array prefixed with ... will expand it’s values. Here’s an example

$parts = ['apple', 'pear'];
$fruits = ['banana', 'orange', ...$parts, 'watermelon'];
// ['banana', 'orange', 'apple', 'pear', 'watermelon'];

Here’s the link to the rfc

Preloading

A new feature that can improve the performance of your code. Preload is implemented as a part of the opcache. Which will generate opcode cache. So all the scripts will be executed once than will be loaded into the memory and later on all the requests will be served from memory. So furture changes that you will do the scripts will not take effect until the server is restarted.