Fatal error: Cannot declare class - php

Question

I can not understand why php gives me an error
"Fatal error: Cannot declare class rex\builder\RexBuilder, because the
name is already in use in /var/www/site2.dev/App/rex/RexBuilder.php on
line 12"
RexBuilder static class, and it is called only 1 time.
I did a search on the project, no longer classes with the same name.
<?php
namespace rex\builder;
require_once 'Router.php';
use rex\router\Router;
error_reporting(E_ALL);
ini_set('display_errors', 1);
class RexBuilder {
public static function collector($array) {
$router = new Router();
foreach ($array as $key => $val) {
$router->get($val->getMethod(), $val->getInterfaces(), $val->getHandler());
}
$router->init();
}
}
?>
Call the class in index.php
RexBuilder::collector(array(
new BuildModel('POST', '/api/v1/user/register', new \api\register\Registration()),
new BuildModel('POST', '/api/v1/user/login', new \api\login\Login())));
More This class is not used

Answer 1

The error is thrown because of the use rex\router\Router; duplicate classes.
When you are writing use namespace.. it means you can go directly to that namespace like it is your current namespace
Lets take a look at the next code:
We'll create a file and declare that it belongs to namespace classes\a
//file: a.php
<?php
namespace classes\a;
class A{
}
now lets create another file b.php (and declare it belongs to namespace classes\b but it means nothing for the example)
namespace classes\b;
require_once "a.php";
use classes\a; //Notice that I'm using this namespace, it means I can use it directly
class A{
}
Generates the error
Fatal error: Cannot declare class classes\b\A because the name is already in use in
We have to solutions possible:
First: remove the use tag and write the namespace directly
class A{
function __constructor(){
$instance = new classes\a\A();
}
}
Second, give it alias
use classes\a as out_a;
class A{
function __constructor(){
$instance = new out_a\A();
}
}
For your code, just remove the use or give it an alias.

Answer 2

The problem is certainly because you include the RexBuilder.php file two times instead of one.
If you call the file by this way : include('RexBuilder.php'); or this way require('RexBuilder.php'); please change it by include_once('RexBuilder.php'); or require_once('RexBuilder.php'); which only allows ONE call of the file.