PHP for people who know how to program  🔗

So, you've chosen / been forced to learn PHP! Congratulations, it's actually not as bad you might have heard.

This guide is a brief introduction

Package managers  🔗

There are two main package managers in PHP, Composer and PECL.

Composer is the package manager used to install userland libraries.

• Commit the composer.lock file to your VCS.

• composer install

PECL is the package manager used to install PHP extensions.

Frameworks  🔗

Laminas  🔗

Laminas is an 'enterprise-ready PHP Framework and components'. Laminas is a continuation of the Zend Framework.

Laravel  🔗

Laravel is an highly opinionated framework for making PHP web applications and set of components.

Slim  🔗

Slim is a PHP micro framework that helps you quickly write simple yet powerful web applications and APIs. For reference, this site uses Slim.

Symfony  🔗

Symfony is an opinionated framework for making PHP web applications and set of components.

High performance frameworks  🔗

As well as traditional 'shared nothing' frameworks, PHP also has some high performance frameworks. These are more difficult to write code for than traditional frameworks, that trade-off is sometimes the correct choice when you have high performance needs.

Amphp  🔗

Amp is an event-driven concurrency framework for PHP providing primitives to manage cooperative multitasking building upon an event loop, and promises.

ReactPHP  🔗

ReactPHP is a low-level library for event-driven programming in PHP. At its core is an event loop, on top of which it provides low-level utilities, ... Third-party libraries can use these components to create async network clients/servers and more.

Swoole  🔗

Build high-performance, scalable, concurrent TCP, UDP, Unix Socket, HTTP, WebSocket services with PHP and easy to use coroutine, fiber API.

Code quality tools  🔗

PHPStan  🔗

Psalm  🔗

Phan  🔗

Infection  🔗

Concepts  🔗

Although PHP is similar to other languages, there are a few concepts/names for things that people should be aware of, that might be difficult to search for.

Autoloading  🔗

PHP is interpreted at runtime. PHP is not compiled like C, Java, Go programs and also isn't built/transpiled like TypeScript/Dart.

Because of this, when the code is run, PHP may need load another file that defines a class/interface if they are not already defined.

For the vast majority of PHP developers, autoloading is taken care by using Composer.

Strict vs weak modes  🔗

PHP can operator in two modes 'strict' and 'weak'. In weak mode, if you pass a parameter to a function of a different type than expected, PHP will do it's best to coerce it into the correct type. For example PHP will coerce a float into an int by rounding it to the nearest int:

<?php

function addNumbers(int $x, int $y): int {
    return $x + $y;
}

echo addNumbers(1, 2);
// output is 3

echo addNumbers(1, 2.4);
// output is also 3, as 2.4 was coerced to an int value of 2 

In strict mode, parameters need to be of the correct type, and passing an incorrect type will lead to a TypeError exception being thrown.

<?php

declare(strict_types = 1);

function addNumbers(int $x, int $y): int {
    return $x + $y;
}

echo addNumbers(1, 2);
// output is 3

echo addNumbers(1, 2.4);

// Fatal error: Uncaught TypeError: addNumbers(): Argument
// #2 ($y) must be of type int, float given

In strict mode there is an exception for promoting ints to floats

<?php

declare(strict_types = 1);

function foo(float $bar): float {
    return $bar;
}

$x = 1;
var_dump($x, foo($x));

// Output is:
// int(1)
// float(1)

By default (i.e. without any declare statement) PHP operates in weak mode.

Core  🔗

TODO...

Userland  🔗

TODO...

Extensions  🔗

TODO...