php - Cannot use X as Y because the name is already in use, even though it's not -

i'm using php 5.4, , have psr-0 class structure similar following.

a\library\session.php:

namespace a\library;  class session { ... }

my\application\session.php:

namespace my\application;  class session { ... }

my\application\facebook.php:

namespace my\application; use a\library\session;  class facebook { ... }

when try run application, following error:

cannot use a\library\session session because name in use in my\application\facebook.php

even though it's not, @ least not in file. facebook.php file declares facebook class, , imports 1 session class, a\library one.

the problem can see session class exists in same namespace facebook class, never imported in facebook.php file, thought did not matter @ all.

am wrong (in case please point relevant documentation), or bug?

there bug confirmed in php may affect behavior see. supposed fatal error, opcache enabled, may still execute flawlessly.

if still concerns you, please vote bug.

Brazier