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+// Copyright Cromwell D. Enage 2013.
+// 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)
+
+#ifndef BOOST_PARAMETER_AUX_PREPROCESSOR_INC_BINARY_SEQ_HPP
+#define BOOST_PARAMETER_AUX_PREPROCESSOR_INC_BINARY_SEQ_HPP
+
+#include <boost/preprocessor/seq/push_back.hpp>
+
+// This macro keeps the rest of the sequence if carry == 0.
+#define BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_0(seq, element) \
+ (BOOST_PP_SEQ_PUSH_BACK(seq, element), 0)
+/**/
+
+#include <boost/preprocessor/control/iif.hpp>
+
+// This macro updates the rest of the sequence if carry == 1.
+#define BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_1(seq, element) \
+ (BOOST_PP_SEQ_PUSH_BACK(seq, BOOST_PP_IIF(element, 0, 1)), element)
+/**/
+
+#include <boost/preprocessor/tuple/elem.hpp>
+#include <boost/preprocessor/cat.hpp>
+
+// This macro maintains a tuple (seq, carry), where seq is the intermediate
+// result and carry is a flag that will unset upon finding an element == 0.
+#define BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_OP(s, result_tuple, element) \
+ BOOST_PP_CAT( \
+ BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_ \
+ , BOOST_PP_TUPLE_ELEM(2, 1, result_tuple) \
+ )(BOOST_PP_TUPLE_ELEM(2, 0, result_tuple), element)
+/**/
+
+// This macro keeps the sequence at its original length if carry == 0.
+#define BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_IMPL_0(seq) seq
+/**/
+
+// This macro appends a zero to seq if carry == 1.
+#define BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_IMPL_1(seq) \
+ BOOST_PP_SEQ_PUSH_BACK(seq, 0)
+/**/
+
+// This macro takes in the tuple (seq, carry), with carry indicating whether
+// or not seq originally contained all 1s. If so, then seq now contains all
+// 0s, and this macro pushes an extra 0 before expanding to the new sequence.
+// Otherwise, this macro expands to seq as is.
+#define BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_IMPL(seq_and_carry) \
+ BOOST_PP_CAT( \
+ BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_IMPL_ \
+ , BOOST_PP_TUPLE_ELEM(2, 1, seq_and_carry) \
+ )(BOOST_PP_TUPLE_ELEM(2, 0, seq_and_carry))
+/**/
+
+#include <boost/preprocessor/seq/seq.hpp>
+#include <boost/preprocessor/seq/fold_left.hpp>
+
+// This macro treats the specified sequence of 1s and 0s like a binary number
+// in reverse and expands to a sequence representing the next value up.
+// However, if the input sequence contains all 1s, then the output sequence
+// will contain one more element but all 0s.
+//
+// Examples:
+// seq = (1)(0)(1)(0) --> return (0)(1)(1)(0)
+// seq = (1)(1)(1)(0) --> return (0)(0)(0)(1)
+// seq = (1)(1)(1)(1) --> return (0)(0)(0)(0)(0)
+#define BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ(seq) \
+ BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_IMPL( \
+ BOOST_PP_SEQ_FOLD_LEFT( \
+ BOOST_PARAMETER_AUX_PP_INC_BINARY_SEQ_OP \
+ , (BOOST_PP_SEQ_NIL, 1) \
+ , seq \
+ ) \
+ )
+/**/
+
+#endif // include guard
+