The current `loadClass()` implementation tries to load a class from the first matching prefix then stops, producing false-negative results. This is especially evident in groups of related libraries, such as Doctrine:
Doctrine
Doctrine\Common
Doctrine\Common\DataFixtures
Doctrine\DBAL
Doctrine\DBAL\Migrations
Each of these libraries is submoduled into a different vendor directory. Depending on what order these libraries are added to a UniversalClassLoader instance, classes may or may not actually be loaded. This fix continues searching registered namespaces and prefixes if the first partial match is negative.
This fixes a bug in UniversalClassLoader when attempting to autoload class names with leading slashes:
$namespacedClass = "\\Foo\\Bar";
$pearlikeClass = "\\Foo_Bar";
$namespaced = new $namespacedClass();
$pearlike = new $pearlikeClass();
`UniversalClassLoader::loadClass()` was unable to load PEAR-like classes with leading slashes because it found the slash and assumed that the requested class was namespaced. It was unable to load namespaced classes with leading slashes because it would look them up in the autoloader's registered namespaces, and was unable to match '\Foo' to 'Foo'. One (ugly) workaround for the namespaced classes was to register all namespaces twice:
$loader->registerNamespaces(array(
'Foo' => __DIR__ . '/lib',
'\Foo' => __DIR__ . '/lib',
));
But that's not very pretty, nor does it solve the bug with PEAR-like classes. Stripping the leading slash before trying to autoload allows UniversalClassLoader to load both namespaced and PEAR-like classes.
