1dnl ------------------------------------------------------------- 2dnl AC_CXX_HAVE_NAMESPACES 3dnl ------------------------------------------------------------- 4AC_DEFUN([AC_CXX_NAMESPACES], 5[AC_CACHE_CHECK(whether the compiler implements namespaces, 6ac_cv_cxx_namespaces, 7[AC_LANG_SAVE 8 AC_LANG_CPLUSPLUS 9 AC_TRY_COMPILE([namespace Outer { namespace Inner { int i = 0; }}], 10 [using namespace Outer::Inner; return i;], 11 ac_cv_cxx_namespaces=yes, ac_cv_cxx_namespaces=no) 12 AC_LANG_RESTORE 13]) 14AS_IF([test "x$ac_cv_cxx_namespaces" = "xyes"], 15 [AC_DEFINE(HAVE_NAMESPACES,,[define if the compiler implements namespaces])]) 16]) 17