# ===========================================================================

#     http://www.gnu.org/software/autoconf-archive/ax_cxx_namespaces.html

# ===========================================================================

#

# SYNOPSIS

#

#   AX_CXX_NAMESPACES

#

# DESCRIPTION

#

#   If the compiler can prevent names clashes using namespaces, define

#   HAVE_NAMESPACES.

#

# LICENSE

#

#   Copyright (c) 2008 Todd Veldhuizen

#   Copyright (c) 2008 Luc Maisonobe <luc@spaceroots.org>

#

#   Copying and distribution of this file, with or without modification, are

#   permitted in any medium without royalty provided the copyright notice

#   and this notice are preserved. This file is offered as-is, without any

#   warranty.

#serial 6

AU_ALIAS([AC_CXX_NAMESPACES], [AX_CXX_NAMESPACES])

AC_DEFUN([AX_CXX_NAMESPACES],

[AC_CACHE_CHECK(whether the compiler implements namespaces,

ax_cv_cxx_namespaces,

[AC_LANG_SAVE

 AC_LANG_CPLUSPLUS

 AC_TRY_COMPILE([namespace Outer { namespace Inner { int i = 0; }}],

                [using namespace Outer::Inner; return i;],

 ax_cv_cxx_namespaces=yes, ax_cv_cxx_namespaces=no)

 AC_LANG_RESTORE

])

if test "$ax_cv_cxx_namespaces" = yes; then

  AC_DEFINE(HAVE_NAMESPACES,1,[define if the compiler implements namespaces])

fi

])