Namespace

Question 1

Namespace syntax (2)

Answer 1

1. namespace Foo\Bar
2. namespace Foo\Bar {
   }// To mix namespace in a single file

Question 2

Mixing namespaced and non-namespaced code in a file

Answer 2

namespace Foo\Bar {
//Namespaced code
}
namespace {
//Non-namespaced code
}

Question 3

Accessing current namespace of subnamespace (2)

Answer 3

namespace\Foo\Bar;

__NAMESPACE__\Foo\Bar;

Question 4

Import a namespaced class A with name B from namespace Foo\Bar

Answer 4

use Foo\Bar\A as B;

Question 5

Import a namespaced function a() with name b() from namespace Foo\Bar

Answer 5

use function Foo\Bar\a as b;

Question 6

Import a namespaced constant A with name B from namespace Foo\Bar

Answer 6

use const Foo\Bar\A as B;

Question 7

Fallback use undefined function in namespace

Answer 7

Try in namespace, if not exist, try in global space