comparison DEPENDENCIES/generic/include/boost/spirit/home/karma/operator/optional.hpp @ 16:2665513ce2d3

Add boost headers

+//  Copyright (c) 2001-2011 Joel de Guzman
+//  Copyright (c) 2001-2011 Hartmut Kaiser
+//
+//  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(SPIRIT_KARMA_OPTIONAL_MARCH_31_2007_0852AM)
+#define SPIRIT_KARMA_OPTIONAL_MARCH_31_2007_0852AM
+
+#if defined(_MSC_VER)
+#pragma once
+#endif
+
+#include <boost/spirit/home/karma/domain.hpp>
+#include <boost/spirit/home/karma/generator.hpp>
+#include <boost/spirit/home/karma/meta_compiler.hpp>
+#include <boost/spirit/home/support/info.hpp>
+#include <boost/spirit/home/support/unused.hpp>
+#include <boost/spirit/home/karma/detail/attributes.hpp>
+#include <boost/spirit/home/support/container.hpp>
+#include <boost/spirit/home/support/has_semantic_action.hpp>
+#include <boost/spirit/home/support/handles_container.hpp>
+#include <boost/mpl/assert.hpp>
+#include <boost/optional.hpp>
+#include <boost/type_traits/is_convertible.hpp>
+
+namespace boost { namespace spirit
+{
+    ///////////////////////////////////////////////////////////////////////////
+    // Enablers
+    ///////////////////////////////////////////////////////////////////////////
+    template <>
+    struct use_operator<karma::domain, proto::tag::negate> // enables -g
+      : mpl::true_ {};
+
+}}
+
+///////////////////////////////////////////////////////////////////////////////
+namespace boost { namespace spirit { namespace karma
+{
+    ///////////////////////////////////////////////////////////////////////////
+    template <typename Subject>
+    struct optional : unary_generator<optional<Subject> >
+    {
+        typedef Subject subject_type;
+        typedef typename subject_type::properties properties;
+
+        // Build a boost::optional from the subject's attribute. Note
+        // that boost::optional may return unused_type if the
+        // subject's attribute is an unused_type.
+        template <typename Context, typename Iterator = unused_type>
+        struct attribute
+          : traits::build_optional<
+                typename traits::attribute_of<Subject, Context, Iterator>::type
+            >
+        {};
+
+        optional(Subject const& subject)
+          : subject(subject) {}
+
+        template <
+            typename OutputIterator, typename Context, typename Delimiter
+          , typename Attribute>
+        bool generate(OutputIterator& sink, Context& ctx
+          , Delimiter const& d, Attribute const& attr) const
+        {
+            if (traits::has_optional_value(attr)) 
+                subject.generate(sink, ctx, d, traits::optional_value(attr));
+            return sink_is_good(sink);
+        }
+
+        template <typename Context>
+        info what(Context& context) const
+        {
+            return info("optional", subject.what(context));
+        }
+
+        Subject subject;
+    };
+
+    ///////////////////////////////////////////////////////////////////////////
+    // Generator generators: make_xxx function (objects)
+    ///////////////////////////////////////////////////////////////////////////
+    template <typename Elements, typename Modifiers>
+    struct make_composite<proto::tag::negate, Elements, Modifiers>
+      : make_unary_composite<Elements, optional> {};
+
+}}}
+
+namespace boost { namespace spirit { namespace traits
+{
+    ///////////////////////////////////////////////////////////////////////////
+    template <typename Subject>
+    struct has_semantic_action<karma::optional<Subject> >
+      : unary_has_semantic_action<Subject> {};
+
+    ///////////////////////////////////////////////////////////////////////////
+    template <typename Subject, typename Attribute, typename Context
+      , typename Iterator>
+    struct handles_container<karma::optional<Subject>, Attribute, Context
+          , Iterator>
+      : mpl::true_ {};
+}}}
+
+#endif