Today, the PHP team has released 7.1.0 that includes new features such as Nullable types, Void return type, Class constant visibility modifiers, and more. Here is a quick overview of some of the new features.
Nullable Types
This adds a leading question mark indicate that a type can also be null.
function answer(): ?int {
return null; //ok
}
function answer(): ?int {
return 42; // ok
}
function answer(): ?int {
return new stdclass(); // error
}
Void Return Type
This requires that a function not return any value:
function should_return_nothing(): void {
return 1; // Fatal error: A void function must not return a value
}
function lacks_return(): void {
// valid
}
function returns_nothing(): void {
return; // valid
}
function returns_null(): void {
return null; // Fatal error: A void function must not return a value
}
Class constant Visibility
You now have the ability to set the visibility on class constants.
class Token {
// Constants default to public
const PUBLIC_CONST = 0;
// Constants then also can have a defined visibility
private const PRIVATE_CONST = 0;
protected const PROTECTED_CONST = 0;
public const PUBLIC_CONST_TWO = 0;
//Constants can only have one visibility declaration list
private const FOO = 1, BAR = 2;
}
For a full list of new features take a look at the release announcement and the changelog. Also, Amo Chohan has a great article highlighting all the changes in PHP 7.1.
