TUPLE_EAT added

[SVN r12295]

include/boost/preprocessor/tuple.hpp

@@ -19,5 +19,6 @@
 Includes all tuple headers.
 */
 
+#include <boost/preprocessor/tuple/eat.hpp>
 #include <boost/preprocessor/tuple/elem.hpp>
 #endif

include/boost/preprocessor/tuple/eat.hpp

@@ -0,0 +1,47 @@
+#ifndef BOOST_PREPROCESSOR_TUPLE_EAT_HPP
+#define BOOST_PREPROCESSOR_TUPLE_EAT_HPP
+
+// Copyright (C) 2001
+// Housemarque Oy
+// http://www.housemarque.com
+//
+// Permission to copy, use, modify, sell and distribute this software is
+// granted provided this copyright notice appears in all copies. This
+// software is provided "as is" without express or implied warranty, and
+// with no claim as to its suitability for any purpose.
+
+// See http://www.boost.org for most recent version.
+
+/*! \file
+
+<a href="../../../../boost/preprocessor/tuple/eat.hpp">Click here to see the header.</a>
+*/
+
+//! Expands to a macro that eats a tuple of the specified length.
+/*!
+BOOST_PP_TUPLE_EAT() is designed to be used with BOOST_PP_IF() like
+BOOST_PP_EMPTY().
+
+For example:
+
+<PRE>\verbatim
+  BOOST_PP_IF(0,BOOST_PP_ENUM_PARAMS,BOOST_PP_TUPLE_EAT(2))(10,P)
+\endverbatim</PRE>
+
+The above expands to nothing.
+*/
+#define BOOST_PP_TUPLE_EAT(N) BOOST_PP_TUPLE_EAT_DELAY(N)
+
+#ifndef DOXYGEN_SHOULD_SKIP_THIS
+#define BOOST_PP_TUPLE_EAT_DELAY(N) BOOST_PP_TUPLE##N##_EAT
+#define BOOST_PP_TUPLE0_EAT()
+#define BOOST_PP_TUPLE1_EAT(A)
+#define BOOST_PP_TUPLE2_EAT(A,B)
+#define BOOST_PP_TUPLE3_EAT(A,B,C)
+#define BOOST_PP_TUPLE4_EAT(A,B,C,D)
+#define BOOST_PP_TUPLE5_EAT(A,B,C,D,E)
+#define BOOST_PP_TUPLE6_EAT(A,B,C,D,E,F)
+#define BOOST_PP_TUPLE7_EAT(A,B,C,D,E,F,G)
+#define BOOST_PP_TUPLE8_EAT(A,B,C,D,E,F,G,H)
+#endif
+#endif

include/boost/preprocessor/while.hpp

@@ -18,6 +18,7 @@
 */
 
 #include <boost/preprocessor/if.hpp>
+#include <boost/preprocessor/tuple/eat.hpp>
 
 //! Iterates F(D,X) while C(D,X) is true.
 /*!
@@ -113,8 +114,7 @@ it possible to compute N*N functions.
 #define BOOST_PP_WHILE(C,F,X) BOOST_PP_WHILE_C(C(1,X),0,X)(C,F,F(1,X))
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
-#define BOOST_PP_WHILE_C(C,D,X) BOOST_PP_IF(C,BOOST_PP_WHILE##D,X BOOST_PP_WHILE_E)
+#define BOOST_PP_WHILE_C(C,D,X) BOOST_PP_IF(C,BOOST_PP_WHILE##D,X BOOST_PP_TUPLE3_EAT)
-#define BOOST_PP_WHILE_E(C,F,X)
 #define BOOST_PP_WHILE0(C,F,X) BOOST_PP_WHILE_C(C(2,X),1,X)(C,F,F(2,X))
 #define BOOST_PP_WHILE1(C,F,X) BOOST_PP_WHILE_C(C(3,X),2,X)(C,F,F(3,X))
 #define BOOST_PP_WHILE2(C,F,X) BOOST_PP_WHILE_C(C(4,X),3,X)(C,F,F(4,X))