Iterables

Iterable is a pseudo-type introduced in PHP 7.1. It accepts any array or object implementing the Traversable interface. Both of these types are iterable using foreach and can be used with yield from within a generator.

Using Iterables

Iterable can be used as a parameter type to indicate that a function requires a set of values, but does not care about the form of the value set since it will be used with foreach. If a value is not an array or instance of Traversable, a TypeError will be thrown.

Example #1 Iterable parameter type example

<?php

function foo(iterable $iterable) {
    foreach (
$iterable as $value) {
        
// ...
    

}

?>

Parameters declared as iterable may use null or an array as a default value.

Example #2 Iterable parameter default value example

<?php

function foo(iterable $iterable = []) {
    
// ...
}

?>

Iterable can also be used as a return type to indicate a function will return an iterable value. If the returned value is not an array or instance of Traversable, a TypeError will be thrown.

Example #3 Iterable return type example

<?php

function bar(): iterable {
    return [
123];
}

?>

Functions declaring iterable as a return type may also be generators.

Example #4 Iterable generator return type example

<?php

function gen(): iterable {
    yield 
1;
    yield 
2;
    yield 
3;
}

?>

Here you can write a comment


Please enter at least 10 characters.
Loading... Please wait.
* Pflichtangabe
There are no comments available yet.

PHP cURL Tutorial: Using cURL to Make HTTP Requests

cURL is a powerful PHP extension that allows you to communicate with different servers using various protocols, including HTTP, HTTPS, FTP, and more. ...

TheMax

Autor : TheMax
Category: PHP-Tutorials

Midjourney Tutorial - Instructions for beginners

There is an informative video about Midjourney, the tool for creating digital images using artificial intelligence, entitled "Midjourney tutorial in German - instructions for beginners" ...

Mike94

Autor : Mike94
Category: KI Tutorials

Basics of views in MySQL

Views in a MySQL database offer the option of creating a virtual table based on the result of an SQL query. This virtual table can be queried like a normal table without changing the underlying data. ...

admin

Autor : admin
Category: mySQL-Tutorials

Publish a tutorial

Share your knowledge with other developers worldwide

Share your knowledge with other developers worldwide

You are a professional in your field and want to share your knowledge, then sign up now and share it with our PHP community

learn more

Publish a tutorial