namespaces.m4 revision bdd62c531bbdea115a3a7e71bba91c19dd319cc4 
1# Checks whether the compiler implements namespaces
2AC_DEFUN([AC_CXX_NAMESPACES],
3 [AC_CACHE_CHECK(whether the compiler implements namespaces,
4                 ac_cv_cxx_namespaces,
5                 [AC_LANG_SAVE
6                  AC_LANG_CPLUSPLUS
7                  AC_TRY_COMPILE([namespace Outer {
8                                    namespace Inner { int i = 0; }}],
9                                 [using namespace Outer::Inner; return i;],
10                                 ac_cv_cxx_namespaces=yes,
11                                 ac_cv_cxx_namespaces=no)
12                  AC_LANG_RESTORE])
13  if test "$ac_cv_cxx_namespaces" = yes; then
14    AC_DEFINE(HAVE_NAMESPACES, 1, [define if the compiler implements namespaces])
15  fi])
16