PHP Fatal error:  require(): Cannot redeclare class composer\composer in phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/vendor/.composer/ClassLoader.php on line 2
PHP Stack trace:
PHP   1. {main}() /Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar:0
PHP   2. require() /Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar:15
PHP   3. Composer\Console\Application->run() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/bin/composer:14
PHP   4. Symfony\Component\Console\Application->run() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Console/Application.php:2
PHP   5. Composer\Console\Application->doRun() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/vendor/symfony/console/Symfony/Component/Console/Application.php:2
PHP   6. Symfony\Component\Console\Application->doRun() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Console/Application.php:2
PHP   7. Symfony\Component\Console\Command\Command->run() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/vendor/symfony/console/Symfony/Component/Console/Application.php:2
PHP   8. Composer\Command\InstallCommand->execute() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/vendor/symfony/console/Symfony/Component/Console/Command/Command.php:2
PHP   9. Composer\Command\InstallCommand->install() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Command/InstallCommand.php:10
PHP  10. Composer\Command\Command->getComposer() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Command/InstallCommand.php:10
PHP  11. Composer\Console\Application->getComposer() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Command/Command.php:2
PHP  12. Composer\Factory::create() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Console/Application.php:2
PHP  13. Composer\Factory->createComposer() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Factory.php:2
PHP  14. Composer\Package\Loader\RootPackageLoader->load() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Factory.php:2
PHP  15. Composer\Package\Loader\ArrayLoader->load() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Package/Loader/RootPackageLoader.php:2
PHP  16. Composer\Package\Loader\ArrayLoader->loadLinksFromConfig() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Package/Loader/ArrayLoader.php:2
PHP  17. Composer\Package\Version\VersionParser->parseConstraints() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Package/Loader/ArrayLoader.php:2
PHP  18. Composer\Package\Version\VersionParser->parseConstraint() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Package/Version/VersionParser.php:2
PHP  19. Composer\Autoload\ClassLoader->loadClass() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/src/Composer/Package/Version/VersionParser.php:0
PHP  20. require() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/vendor/.composer/ClassLoader.php:2
PHP  21. Composer\Autoload\ClassLoader->loadClass() phar:///Users/romainpouclet/Sites/KNP/knpuniversity_api/composer.phar/vendor/.composer/ClassLoader.php:0