https://github.com/aimeos/macro
Customize code using closures
https://github.com/aimeos/macro
class closure custom customize dynamic extend inherit macro macros php
Last synced: 11 days ago
JSON representation
Customize code using closures
- Host: GitHub
- URL: https://github.com/aimeos/macro
- Owner: aimeos
- License: mit
- Created: 2021-12-02T07:17:00.000Z (over 3 years ago)
- Default Branch: master
- Last Pushed: 2024-11-07T11:21:21.000Z (7 months ago)
- Last Synced: 2025-04-30T15:17:57.508Z (24 days ago)
- Topics: class, closure, custom, customize, dynamic, extend, inherit, macro, macros, php
- Language: PHP
- Homepage: https://php-macro.org
- Size: 80.1 KB
- Stars: 1,713
- Watchers: 3
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
## PHP Macro
The PHP Macro package offers closure (anonymous function) based setter dependency
injection by providing a trait which can be included into any class.
```bash
composer req aimeos/macro
```
This package is for application, framework and library developers who want to
allow customizing the behavior of their code by their users.
## Why macros
In applications, frameworks or libraries which are build for customization it’s
necessary to allow overwriting existing functionality to be able customize its
behavior. This is where macros are very handy because they can add custom code
using closures.
With the PHP Macro package, you can also allow users to overwrite methods in
base classes without forcing your users to extend these classes. The PHP Macro
package uses **NO reflection** or other hacks, just **pure PHP methods**.
There are some pros and cons when compared to class based depencency injection:
**Pro:**
* Less code to write and much easier to implement for simple stuff
* Custom closures can be inherited and overwritten like class methods
**Con:**
* Limited static code analysis possibilities
* Anonymous function can not be forced to implement an interface
Thus, it's not a replacement for class based depencency injection but a lightweight
addition for small extension points where full-blown dependency injection using
classes implementing interfaces are too much work.
## Allow customization
The result of existing methods can be modified if the original method checks
for an existing macro and use that instead its own implementation:
```php
// original code
class Order
{
use Aimeos\Macro\Macroable;
private $id = '123';
public function getOrderNumber()
{
$fcn = static::macro( 'orderNumber' );
return $fcn ? $fcn( $this->id ) : $this->id;
}
};
```
Now, you can add your custom `orderNumber` macro that will be used instead:
```php
// user code
Order::macro( 'orderNumber', function( string $id ) {
return date( 'Y' ) . '-' . $id;
} );
(new Order)->getOrderNumber(); // now returns '2020-123'
```
Thus, you can generate own output or pass a different result to subseqent methods
within the application.
## Access class properties
When macros are called in an object context, they can also access class properties:
```php
// original code
class A
{
use Aimeos\Macro\Macroable;
private $name = 'A';
};
```
Here, the private property `$name` is available in the macro:
```php
// user code
A::macro( 'concat', function( array $values ) {
return $this->name . ':' . implode( '-', $values );
} );
(new A)->concat( ['1', '2', '3'] ); // returns 'A:1-2-3'
```
The macro can use the property as input for creating the returned value.
## Use inherited macros
The PHP macro package also allows to inherit macros from parent classes. Then,
they can access class properties of the child class just like regular class
methods:
```php
// original code
class A
{
use Aimeos\Macro\Macroable;
private $name = 'A';
};
class B extends A
{
private $name = 'B';
};
```
Macros added to the parent class will be available in child classes too:
```php
// user code
A::macro( 'concat', function( array $values ) {
return $this->name . ':' . implode( '-', $values );
} );
(new B)->concat( ['1', '2', '3'] ); // returns 'B:1-2-3'
```
Class `B` extends from class `A` but provides a different `$name` property. The
macro inherited from class `A` will now use the property of class `B`.
## Overwrite inherited macros
It's also possible to overwrite macros inherited from parent classes as it's
possible with regular class methods:
```php
// original code
class A
{
use Aimeos\Macro\Macroable;
public function do() {
return static::macro( 'concat' )( [1, 2, 3] );
}
};
class B extends A {};
class C extends A {};
```
Now you can add macros to the parent class and one of the child classes:
```php
// user code
A::macro( 'concat', function( array $values ) {
return implode( ',', $values );
} );
C::macro( 'concat', function( array $values ) {
return implode( '-', $values );
} );
(new B)->do(); // returns '1,2,3'
(new C)->do(); // returns '1-2-3'
```
This enables you to add special handling for single classes even if all other
classes still use the macro added to class `A`.
## Overwrite protected methods
Base classes often offer a set of methods that are used by the child classes.
In PHP, replacing the methods of a base class is impossible and thus, you have
to overwrite each child class with your own implementation.
To avoid that, the original method can use the `call()` method instead of calling
the method of the parent class directly:
```php
// original code
class A
{
use Aimeos\Macro\Macroable;
protected function getName( $prefix )
{
return $prefix . 'A';
}
};
class B extends A
{
public function do()
{
return $this->call( 'getName', 'B-' );
}
};
```
This will check if there's a macro `getName` available and will call that instead
of the `getName()` method:
```php
// user code
(new B)->do(); // returns 'B-A'
A::macro( 'getName', function( $prefix ) {
return $this->getName( $prefix ) . '-123';
} );
(new B)->do(); // returns 'B-A-123'
```
The original `getName()` method can still be used in the macro.
## Reset macros
Sometimes, it may be necessary to remove macros from objects, especially when
running automated tests. You can unset a macro by using:
```php
class A
{
use Aimeos\Macro\Macroable;
};
// add macro
A::macro( 'test', function() {
return 'test';
} );
// remove macro
A::unmacro( 'test' );
```