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diff --git a/boost/spirit/home/x3/auxiliary/eps.hpp b/boost/spirit/home/x3/auxiliary/eps.hpp
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+++ b/boost/spirit/home/x3/auxiliary/eps.hpp
@@ -0,0 +1,92 @@
+/*=============================================================================
+    Copyright (c) 2001-2014 Joel de Guzman
+
+    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)
+==============================================================================*/
+#if !defined(BOOST_SPIRIT_X3_EPS_MARCH_23_2007_0454PM)
+#define BOOST_SPIRIT_X3_EPS_MARCH_23_2007_0454PM
+
+#if defined(_MSC_VER)
+#pragma once
+#endif
+
+#include <boost/spirit/home/x3/core/skip_over.hpp>
+#include <boost/spirit/home/x3/core/parser.hpp>
+#include <boost/spirit/home/x3/support/unused.hpp>
+
+namespace boost { namespace spirit { namespace x3
+{
+    struct rule_context_tag;
+
+    struct semantic_predicate : parser<semantic_predicate>
+    {
+        typedef unused_type attribute_type;
+        static bool const has_attribute = false;
+
+        semantic_predicate(bool predicate)
+          : predicate(predicate) {}
+
+        template <typename Iterator, typename Context, typename Attribute>
+        bool parse(Iterator& first, Iterator const& last
+          , Context const& context, unused_type, Attribute&) const
+        {
+            x3::skip_over(first, last, context);
+            return predicate;
+        }
+
+        bool predicate;
+    };
+
+    template <typename F>
+    struct lazy_semantic_predicate : parser<lazy_semantic_predicate<F>>
+    {
+        typedef unused_type attribute_type;
+        static bool const has_attribute = false;
+
+        lazy_semantic_predicate(F f)
+          : f(f) {}
+
+        template <typename Iterator, typename Context, typename Attribute>
+        bool parse(Iterator& first, Iterator const& last
+          , Context const& context, unused_type, Attribute& attr) const
+        {
+            x3::skip_over(first, last, context);
+            return f(x3::get<rule_context_tag>(context));
+        }
+
+        F f;
+    };
+
+    struct eps_parser : parser<eps_parser>
+    {
+        typedef unused_type attribute_type;
+        static bool const has_attribute = false;
+
+        template <typename Iterator, typename Context
+          , typename RuleContext, typename Attribute>
+        bool parse(Iterator& first, Iterator const& last
+          , Context const& context, RuleContext&, Attribute&) const
+        {
+            x3::skip_over(first, last, context);
+            return true;
+        }
+
+        semantic_predicate
+        operator()(bool predicate) const
+        {
+            return semantic_predicate(predicate);
+        }
+
+        template <typename F>
+        lazy_semantic_predicate<F>
+        operator()(F f) const
+        {
+            return lazy_semantic_predicate<F>(f);
+        }
+    };
+
+    eps_parser const eps = eps_parser();
+}}}
+
+#endif