use and require_once in PHP

Question

I would like to know why I should use require_once if I use namespaces ? What is the point of the 'use' keyword and namespaces if I have to use require_once. (I understand it is a different way of thinking from Java import and packages)

Accepted Answer

There are no relations between namespaces/use(importing classes/namespaces) and the require/include (_once or not) family of functions.

If you do use an autoload that is PSR-0 or PSR-4 compatible such as Composer's autoloader, then you should not need to use require/include to get some classes into your code.

Namespaces allow you to divide your code into different sections in memory to prevent clashing of class/function names. Use is a keyword that imports existing namespaced entities into the current namespace scope of the file (each file may have only one namespace) which will prevent you from having to supply the complete path to a class or function name:

```
namespace \My\Namespace\Path;
use \My\Other\Namespace\Path;
use \My\Last\Namespace\ClassName;
```

You can now use anything from \My\Other\Namespace\Path in the current namespace without specifying the whole path.

use and require_once in PHP

Solution

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