PHP Code Generator

Installation

Download and install the package using Composer:

composer require nette/php-generator

For PHP compatibility, see the table.

Classes

Let's start with a straightforward example of generating class using ClassType:

$class = new Nette\PhpGenerator\ClassType('Demo');

$class
	->setFinal()
	->setExtends(ParentClass::class)
	->addImplement(Countable::class)
	->addComment("Description of class.\nSecond line\n")
	->addComment('@property-read Nette\Forms\Form $form');

// to generate PHP code simply cast to string or use echo:
echo $class;

It will render this result:

/**
 * Description of class.
 * Second line
 *
 * @property-read Nette\Forms\Form $form
 */
final class Demo extends ParentClass implements Countable
{
	use Nette\SmartObject;
}

We can also use a printer to generate the code, which, unlike echo $class, we will be able to further configure:

$printer = new Nette\PhpGenerator\Printer;
echo $printer->printClass($class);

We can add constants (class Constant) and properties (class Property):

$class->addConstant('ID', 123)
	->setProtected() // constant visibility
	->setFinal();

$class->addProperty('items', [1, 2, 3])
	->setPrivate() // or setVisibility('private')
	->setStatic()
	->addComment('@var int[]');

$class->addProperty('list')
	->setType('?array')
	->setInitialized(); // prints '= null'

It generates:

final protected const ID = 123;

/** @var int[] */
private static $items = [1, 2, 3];

public ?array $list = null;

And we can add methods:

$method = $class->addMethod('count')
	->addComment('Count it.')
	->setFinal()
	->setProtected()
	->setReturnType('?int') // method return type
	->setBody('return count($items ?: $this->items);');

$method->addParameter('items', []) // $items = []
	->setReference()           // &$items = []
	->setType('array');        // array &$items = []

It results in:

/**
 * Count it.
 */
final protected function count(array &$items = []): ?int
{
	return count($items ?: $this->items);
}

Promoted parameters introduced by PHP 8.0 can be passed to the constructor (since v3.5):

$method = $class->addMethod('__construct');
$method->addPromotedParameter('name');
$method->addPromotedParameter('args', [])
	->setPrivate();

It results in:

public function __construct(
	public $name,
	private $args = [],
) {
}

Readonly properties introduced by PHP 8.1 can be marked via setReadOnly().

If the added property, constant, method or parameter already exist, it will be overwritten.

Members can be removed using removeProperty(), removeConstant(), removeMethod() or removeParameter().

You can also add existing Method, Property or Constant objects to the class:

$method = new Nette\PhpGenerator\Method('getHandle');
$property = new Nette\PhpGenerator\Property('handle');
$const = new Nette\PhpGenerator\Constant('ROLE');

$class = (new Nette\PhpGenerator\ClassType('Demo'))
	->addMember($method)
	->addMember($property)
	->addMember($const);

You can clone existing methods, properties and constants with a different name using cloneWithName():

$methodCount = $class->getMethod('count');
$methodRecount = $methodCount->cloneWithName('recount');
$class->addMember($methodRecount);

Interface or Trait

You can create interfaces and traits:

$interface = Nette\PhpGenerator\ClassType::interface('MyInterface');
$trait = Nette\PhpGenerator\ClassType::trait('MyTrait');

Using Traits:

$class = new Nette\PhpGenerator\ClassType('Demo');
$class->addTrait('SmartObject');
$class->addTrait('MyTrait')
	->addResolution('sayHello as protected')
	->addComment('@use MyTrait<Foo>');
echo $class;

Result:

class Demo
{
	use SmartObject;
	use MyTrait {
		sayHello as protected;
	}
}

Enums

You can easily create the enums that PHP 8.1 brings:

$enum = Nette\PhpGenerator\ClassType::enum('Suit');
$enum->addCase('Clubs');
$enum->addCase('Diamonds');
$enum->addCase('Hearts');
$enum->addCase('Spades');

echo $enum;

Result:

enum Suit
{
	case Clubs;
	case Diamonds;
	case Hearts;
	case Spades;
}

You can also define scalar equivalents for cases to create a backed enum:

$enum->addCase('Clubs', '♣');
$enum->addCase('Diamonds', '♦');

It is possible to add a comment or attributes to each case using addComment() or addAttribute().

Anonymous Class

Give null as the name and you have an anonymous class:

$class = new Nette\PhpGenerator\ClassType(null);
$class->addMethod('__construct')
	->addParameter('foo');

echo '$obj = new class ($val) ' . $class . ';';

Result:

$obj = new class ($val) {

	public function __construct($foo)
	{
	}
};

Global Function

Code of functions will generate class GlobalFunction:

$function = new Nette\PhpGenerator\GlobalFunction('foo');
$function->setBody('return $a + $b;');
$function->addParameter('a');
$function->addParameter('b');
echo $function;

// or use PsrPrinter for output conforming to PSR-2 / PSR-12
// echo (new Nette\PhpGenerator\PsrPrinter)->printFunction($function);

Result:

function foo($a, $b)
{
	return $a + $b;
}

Closure

Code of closures will generate class Closure:

$closure = new Nette\PhpGenerator\Closure;
$closure->setBody('return $a + $b;');
$closure->addParameter('a');
$closure->addParameter('b');
$closure->addUse('c')
	->setReference();
echo $closure;

// or use PsrPrinter for output conforming to PSR-2 / PSR-12
// echo (new Nette\PhpGenerator\PsrPrinter)->printClosure($closure);

Result:

function ($a, $b) use (&$c) {
	return $a + $b;
}

Arrow Function

You can also print closure as arrow function using printer:

$closure = new Nette\PhpGenerator\Closure;
$closure->setBody('$a + $b');
$closure->addParameter('a');
$closure->addParameter('b');

echo (new Nette\PhpGenerator\Printer)->printArrowFunction($closure);

Result:

fn($a, $b) => $a + $b

Method and Function Signature

Methods are represented by the class Method. You can set visibility, return value, add comments, attributes etc:

$method = $class->addMethod('count')
	->addComment('Count it.')
	->setFinal()
	->setProtected()
	->setReturnType('?int');

Each parameter is represented by a class Parameter. Again, you can set every conceivable property:

$method->addParameter('items', []) // $items = []
	->setReference() // &$items = []
	->setType('array'); // array &$items = []

// function count(&$items = [])

To define the so-called variadics parameters (or also the splat, spread, ellipsis, unpacking or three dots operator), use setVariadics():

$method = $class->addMethod('count');
$method->setVariadics(true);
$method->addParameter('items');

Generates:

function count(...$items)
{
}

Method and Function Body

The body can be passed to the setBody() method at once or sequentially (line by line) by repeatedly calling addBody():

$function = new Nette\PhpGenerator\GlobalFunction('foo');
$function->addBody('$a = rand(10, 20);');
$function->addBody('return $a;');
echo $function;

Result

function foo()
{
	$a = rand(10, 20);
	return $a;
}

You can use special placeholders for handy way to inject variables.

Simple placeholders ?

$str = 'any string';
$num = 3;
$function = new Nette\PhpGenerator\GlobalFunction('foo');
$function->addBody('return substr(?, ?);', [$str, $num]);
echo $function;

Result:

function foo()
{
	return substr('any string', 3);
}

Variadic placeholder ...?

$items = [1, 2, 3];
$function = new Nette\PhpGenerator\GlobalFunction('foo');
$function->setBody('myfunc(...?);', [$items]);
echo $function;

Result:

function foo()
{
	myfunc(1, 2, 3);
}

You can also use PHP 8 named parameters using placeholder ...?:

$items = ['foo' => 1, 'bar' => true];
$function->setBody('myfunc(...?:);', [$items]);

// myfunc(foo: 1, bar: true);

Escape placeholder using slash \?

$num = 3;
$function = new Nette\PhpGenerator\GlobalFunction('foo');
$function->addParameter('a');
$function->addBody('return $a \? 10 : ?;', [$num]);
echo $function;

Result:

function foo($a)
{
	return $a ? 10 : 3;
}

Printers and PSR Compliance

PHP code is generated by Printer objects. There is a PsrPrinter whose output conforms to PSR-2 and PSR-12 and uses spaces for indentation, and a Printer that uses tabs for indentation.

$class = new Nette\PhpGenerator\ClassType('Demo');
// ...

$printer = new Nette\PhpGenerator\PsrPrinter;
echo $printer->printClass($class); // 4 spaces indentation

Need to customize printer behavior? Create your own by inheriting the Printer class. You can reconfigure these variables:

class MyPrinter extends Nette\PhpGenerator\Printer
{
	protected $indentation = "\t";
	protected $linesBetweenProperties = 0;
	protected $linesBetweenMethods = 1;
	protected $returnTypeColon = ': ';
}

Types

Each type or union/intersection type can be passed as a string, you can also use predefined constants for native types:

use Nette\PhpGenerator\Type;

$member->setType('array'); // or Type::ARRAY;
$member->setType('array|string'); // or Type::union('array', 'string')
$member->setType('Foo&Bar'); // or Type::intersection(Foo::class, Bar::class)
$member->setType(null); // removes type

The same applies to the method setReturnType().

Literals

With Literal you can pass arbitrary PHP code to, for example, default property or parameter values etc:

use Nette\PhpGenerator\Literal;

$class = new Nette\PhpGenerator\ClassType('Demo');

$class->addProperty('foo', new Literal('Iterator::SELF_FIRST'));

$class->addMethod('bar')
	->addParameter('id', new Literal('1 + 2'));

echo $class;

Result:

class Demo
{
	public $foo = Iterator::SELF_FIRST;

	public function bar($id = 1 + 2)
	{
	}
}

You can also pass parameters to Literal and have it formatted into valid PHP code using special placeholders:

new Literal('substr(?, ?)', [$a, $b]);
// generates, for example: substr('hello', 5);

Attributes

You can add PHP 8 attributes to all classes, methods, properties, constants, enum cases, functions, closures and parameters. Literals can also be used as parameter values.

$class = new Nette\PhpGenerator\ClassType('Demo');
$class->addAttribute('Deprecated');

$class->addProperty('list')
	->addAttribute('WithArguments', [1, 2]);

$method = $class->addMethod('count')
	->addAttribute('Foo\Cached', ['mode' => true]);

$method->addParameter('items')
	->addAttribute('Bar');

echo $class;

Result:

#[Deprecated]
class Demo
{
	#[WithArguments(1, 2)]
	public $list;


	#[Foo\Cached(mode: true)]
	public function count(#[Bar] $items)
	{
	}
}

Namespace

Classes, traits, interfaces and enums (hereinafter classes) can be grouped into namespaces (PhpNamespace):

$namespace = new Nette\PhpGenerator\PhpNamespace('Foo');

// create new classes in the namespace
$class = $namespace->addClass('Task');
$interface = $namespace->addInterface('Countable');
$trait = $namespace->addTrait('NameAware');

// or insert an existing class into the namespace
$class = new Nette\PhpGenerator\ClassType('Task');
$namespace->add($class);

If the class already exists, it will be overwritten.

You can define use-statements:

// use Http\Request;
$namespace->addUse(Http\Request::class);
// use Http\Request as HttpReq;
$namespace->addUse(Http\Request::class, 'HttpReq');
// use function iter\range;
$namespace->addUseFunction('iter\range');

To simplify a fully qualified class, function or constant name according to the defined aliases, use the simplifyName method:

echo $namespace->simplifyName('Foo\Bar'); // 'Bar', because 'Foo' is current namespace
echo $namespace->simplifyName('iter\range', $namespace::NAME_FUNCTION); // 'range', because of the defined use-statement

Conversely, you can convert a simplified class, function or constant name to a fully qualified one using the resolveName method:

echo $namespace->resolveName('Bar'); // 'Foo\Bar'
echo $namespace->resolveName('range', $namespace::NAME_FUNCTION); // 'iter\range'

Class Names Resolving

When the class is part of the namespace, it is rendered slightly differently: all types (ie. type hints, return types, parent class name, implemented interfaces, used traits and attributes) are automatically resolved (unless you turn it off, see below). It means that you have to use full class names in definitions and they will be replaced with aliases (according to the use-statements) or fully qualified names in the resulting code:

$namespace = new Nette\PhpGenerator\PhpNamespace('Foo');
$namespace->addUse('Bar\AliasedClass');

$class = $namespace->addClass('Demo');
$class->addImplement('Foo\A') // it will simplify to A
	->addTrait('Bar\AliasedClass'); // it will simplify to AliasedClass

$method = $class->addMethod('method');
$method->addComment('@return ' . $namespace->simplifyName('Foo\D')); // in comments simplify manually
$method->addParameter('arg')
	->setType('Bar\OtherClass'); // it will resolve to \Bar\OtherClass

echo $namespace;

// or use PsrPrinter for output conforming to PSR-2 / PSR-12
// echo (new Nette\PhpGenerator\PsrPrinter)->printNamespace($namespace);

Result:

namespace Foo;

use Bar\AliasedClass;

class Demo implements A
{
	use AliasedClass;

	/**
	 * @return D
	 */
	public function method(\Bar\OtherClass $arg)
	{
	}
}

Auto-resolving can be turned off this way:

$printer = new Nette\PhpGenerator\Printer; // or PsrPrinter
$printer->setTypeResolving(false);
echo $printer->printNamespace($namespace);

PHP Files

Classes, functions and namespaces can be grouped into PHP files represented by the class PhpFile:

$file = new Nette\PhpGenerator\PhpFile;
$file->addComment('This file is auto-generated.');
$file->setStrictTypes(); // adds declare(strict_types=1)

$class = $file->addClass('Foo\A');
$function = $file->addFunction('Foo\foo');

// or
// $namespace = $file->addNamespace('Foo');
// $class = $namespace->addClass('A');
// $function = $namespace->addFunction('foo');

echo $file;

// or use PsrPrinter for output conforming to PSR-2 / PSR-12
// echo (new Nette\PhpGenerator\PsrPrinter)->printFile($file);

Result:

<?php

/**
 * This file is auto-generated.
 */

declare(strict_types=1);

namespace Foo;

class A
{
}

function foo()
{
}

Generating According to Existing Ones

In addition to being able to model classes and functions using the API described above, you can also have them automatically generated using existing ones:

// creates a class identical to the PDO class
$class = Nette\PhpGenerator\ClassType::from(PDO::class);

// creates a function identical to trim()
$function = Nette\PhpGenerator\GlobalFunction::from('trim');

// creates a closure as specified
$closure = Nette\PhpGenerator\Closure::from(
	function (stdClass $a, $b = null) {}
);

Function and method bodies are empty by default. If you want to load them as well, use this way (it requires nikic/php-parser to be installed and PhpGenerator version 3.4):

$class = Nette\PhpGenerator\ClassType::withBodiesFrom(MyClass::class);

$function = Nette\PhpGenerator\GlobalFunction::withBodyFrom('dump');

Loading from PHP File

You can also load classes and functions directly from a PHP file that is not already loaded or string of PHP code:

$class = Nette\PhpGenerator\ClassType::fromCode(<<<XX
	<?php

	class Demo
	{
		public $foo;
	}
	XX);

Loading the entire PHP file, which may contain multiple classes or even multiple namespaces:

$file = Nette\PhpGenerator\PhpFile::fromCode(file_get_contents('classes.php'));

This requires nikic/php-parser to be installed.

Variables Dumper

The Dumper returns a parsable PHP string representation of a variable. Provides better and clearer output that native function var_export().

$dumper = new Nette\PhpGenerator\Dumper;

$var = ['a', 'b', 123];

echo $dumper->dump($var); // prints ['a', 'b', 123]

Compatibility Table