doc: entt namespace in-source doc

docs/CMakeLists.txt

@@ -32,7 +32,6 @@ if(DOXYGEN_FOUND)
         WORKING_DIRECTORY ${EnTT_SOURCE_DIR}
         VERBATIM
         SOURCES
-            dox/extra.dox
             md/config.md
             md/container.md
             md/core.md

docs/dox/extra.dox

@@ -1,5 +0,0 @@
-/**
- * @namespace entt
- *
- * @brief `EnTT` default namespace.
- */

docs/doxy.in

@@ -983,8 +983,7 @@ INPUT_FILE_ENCODING    =
 
 FILE_PATTERNS          = *.h \
                          *.hpp \
-                         *.md \
-                         *.dox
+                         *.md
 
 # The RECURSIVE tag can be used to specify whether or not subdirectories should
 # be searched for input files as well.

src/entt/entt.hpp

@@ -1,3 +1,6 @@
+/*! @brief `EnTT` default namespace. */
+namespace entt {}
+
 // IWYU pragma: begin_exports
 #include "config/config.h"
 #include "config/macro.h"