Initial implementation of exclusive definition of compiler detection

with emulated definitions.

include/boost/predef/compiler/watcom.h

@@ -1,5 +1,5 @@
 /*
-Copyright Rene Rivera 2008-2013
+Copyright Rene Rivera 2008-2014
 Distributed under the Boost Software License, Version 1.0.
 (See accompanying file LICENSE_1_0.txt or copy at
 http://www.boost.org/LICENSE_1_0.txt)
@@ -29,12 +29,18 @@ Version number available as major, and minor.
 #define BOOST_COMP_WATCOM BOOST_VERSION_NUMBER_NOT_AVAILABLE
 
 #if defined(__WATCOMC__)
-#   undef BOOST_COMP_WATCOM
-#   define BOOST_COMP_WATCOM BOOST_PREDEF_MAKE_10_VVRR(__WATCOMC__)
+#   define BOOST_COMP_WATCOM_DETECTION BOOST_PREDEF_MAKE_10_VVRR(__WATCOMC__)
 #endif
 
-#if BOOST_COMP_WATCOM
+#ifdef BOOST_COMP_WATCOM_DETECTION
+#   if defined(BOOST_PREDEF_DETAIL_COMP_DETECTED)
+#       define BOOST_COMP_WATCOM_EMULATED BOOST_COMP_WATCOM_DETECTION
+#   else
+#       undef BOOST_COMP_WATCOM
+#       define BOOST_COMP_WATCOM BOOST_COMP_WATCOM_DETECTION
+#   endif
 #   define BOOST_COMP_WATCOM_AVAILABLE
+#   include <boost/predef/detail/comp_detected.h>
 #endif
 
 #define BOOST_COMP_WATCOM_NAME "Watcom C++"
@@ -42,5 +48,10 @@ Version number available as major, and minor.
 #include <boost/predef/detail/test.h>
 BOOST_PREDEF_DECLARE_TEST(BOOST_COMP_WATCOM,BOOST_COMP_WATCOM_NAME)
 
+#ifdef BOOST_COMP_WATCOM_EMULATED
+#include <boost/predef/detail/test.h>
+BOOST_PREDEF_DECLARE_TEST(BOOST_COMP_WATCOM_EMULATED,BOOST_COMP_WATCOM_NAME)
+#endif
+
 
 #endif