# Check for standard iterator extension.  This is modified from
# http://www.gnu.org/software/ac-archive/htmldoc/ac_cxx_have_ext_hash_set.html
AC_DEFUN([AC_CXX_HAVE_STD_ITERATOR],
[AC_CACHE_CHECK(whether the compiler has the standard iterator,
ac_cv_cxx_have_std_iterator,
[AC_REQUIRE([AC_CXX_NAMESPACES])
  AC_LANG_PUSH([C++])
  AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
    [[#include <iterator>
#ifdef HAVE_NAMESPACES
using namespace std;
#endif]],
  [[iterator<int,int,int> t; return 0;]])],
  ac_cv_cxx_have_std_iterator=yes, 
  ac_cv_cxx_have_std_iterator=no)
  AC_LANG_POP([C++])
])
if test "$ac_cv_cxx_have_std_iterator" = yes
then
   AC_DEFINE(HAVE_STD_ITERATOR,1,[Have std namespace iterator])
else
   AC_DEFINE(HAVE_STD_ITERATOR,0,[Does not have std namespace iterator])
fi
])