protected static function psr_classloader($class) {
        // Iterate through each PSR-4 namespace prefix.
        foreach (self::$psr4namespaces as $prefix => $path) {
            $file = self::get_class_file($class, $prefix, $path, array('\\'));
            if (!empty($file) && file_exists($file)) {
                return $file;
            }
        }

        // Iterate through each PSR-0 namespace prefix.
        foreach (self::$psr0namespaces as $prefix => $path) {
            $file = self::get_class_file($class, $prefix, $path, array('\\', '_'));
            if (!empty($file) && file_exists($file)) {
                return $file;
            }
        }

        return false;
    }
protected static function psr_classloader($class) {
        // Iterate through each PSR-4 namespace prefix.
        foreach (self::$psr4namespaces as $prefix => $path) {
            $file = self::get_class_file($class, $prefix, $path, array('\\'));
            if (!empty($file) && file_exists($file)) {
                return $file;
            }
        }

        // Iterate through each PSR-0 namespace prefix.
        foreach (self::$psr0namespaces as $prefix => $path) {
            $file = self::get_class_file($class, $prefix, $path, array('\\', '_'));
            if (!empty($file) && file_exists($file)) {
                return $file;
            }
        }

        return false;
    }
protected static function psr_classloader ( $ class ) { // Iterate through each PSR-4 namespace prefix. foreach ( self :: $ psr4namespaces as $ prefix => $ path ) { $ file = self :: get_class_file ( $ class , $ prefix , $ path , array ( '\\' ) ) ; if ( ! empty ( $ file ) && file_exists ( $ file ) ) { return $ file ; } } // Iterate through each PSR-0 namespace prefix. foreach ( self :: $ psr0namespaces as $ prefix => $ path ) { $ file = self :: get_class_file ( $ class , $ prefix , $ path , array ( '\\' , '_' ) ) ; if ( ! empty ( $ file ) && file_exists ( $ file ) ) { return $ file ; } } return false ; }
Return the path to a class from our defined PSR-0 or PSR-4 standard namespaces on
demand. Only returns paths to files that exist.

Adapated from http://www.php-fig.org/psr/psr-4/examples/ and made PSR-0
compatible.

@param string $class the name of the class.
@return string|bool The full path to the file defining the class. Or false if it could not be resolved or does not exist.
Return the path to a class from our defined PSR - 0 or PSR - 4 standard namespaces on demand . Only returns paths to files that exist .