autoconf/m4/cxx_fwd_iterator.m4

   1 # Check for forward iterator extension.  This is modified from
   2 # http://www.gnu.org/software/ac-archive/htmldoc/ac_cxx_have_ext_hash_set.html
   3 AC_DEFUN([AC_CXX_HAVE_FWD_ITERATOR],
   4 [AC_CACHE_CHECK(whether the compiler has forward iterators,
   5 ac_cv_cxx_have_fwd_iterator,
   6 [AC_REQUIRE([AC_CXX_NAMESPACES])
   7   AC_LANG_PUSH([C++])
   8   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <iterator>
   9 #ifdef HAVE_NAMESPACES
  10 using namespace std;
  11 #endif]], [[forward_iterator<int,int> t; return 0;]])],[ac_cv_cxx_have_fwd_iterator=yes],[ac_cv_cxx_have_fwd_iterator=no])
  12   AC_LANG_POP([C++])
  13 ])
  14 if test "$ac_cv_cxx_have_fwd_iterator" = yes
  15 then
  16    AC_DEFINE(HAVE_FWD_ITERATOR,1,[Have forward iterator])
  17 else
  18    AC_DEFINE(HAVE_FWD_ITERATOR,0,[Does not have forward iterator])
  19 fi
  20 ])
  21
  22