This code works without problems:
<?php
namespace NamespaceA;
class A extends \NamespaceB\B {}
namespace NamespaceB;
class B {}
But why the following code cause Fatal error: Class 'NamespaceB\B' not found in ...file?
<?php
namespace NamespaceA;
class A extends \NamespaceB\B {}
namespace NamespaceB;
class B extends \NamespaceC\C {}
namespace NamespaceC;
class C {}
And this code also works without problems:
<?php
namespace NamespaceA;
class A extends \NamespaceB\B {}
namespace NamespaceC;
class C {}
namespace NamespaceB;
class B extends \NamespaceC\C {}
Without any namespace, also Fatal error: Class 'B' not found in ...file:
<?php
class A extends B {}
class B extends C {}
class C {}
Works without problems:
<?php
class A extends B {}
class B {}
And yes everything is in the same PHP file....