Subject: [Boost-commit] svn:boost r63316 - sandbox/variadic_templates/boost/composite_storage
From: cppljevans_at_[hidden]
Date: 2010-06-25 14:10:30
Author: cppljevans
Date: 2010-06-25 14:10:29 EDT (Fri, 25 Jun 2010)
New Revision: 63316
URL: http://svn.boost.org/trac/boost/changeset/63316
Log:
top-directory files
Added:
sandbox/variadic_templates/boost/composite_storage/enum_base.hpp (contents, props changed)
sandbox/variadic_templates/boost/composite_storage/functor_indexed.hpp (contents, props changed)
sandbox/variadic_templates/boost/composite_storage/special_components.hpp (contents, props changed)
sandbox/variadic_templates/boost/composite_storage/tags.hpp (contents, props changed)
Added: sandbox/variadic_templates/boost/composite_storage/enum_base.hpp
==============================================================================
--- (empty file)
+++ sandbox/variadic_templates/boost/composite_storage/enum_base.hpp 2010-06-25 14:10:29 EDT (Fri, 25 Jun 2010)
@@ -0,0 +1,30 @@
+//meta function returning the base of an enumeration.
+#ifndef BOOST_COMPOSITE_STORAGE_ENUM_BASE_HPP_INCLUDED
+#define BOOST_COMPOSITE_STORAGE_ENUM_BASE_HPP_INCLUDED
+#include <boost/mpl/integral_c.hpp>
+
+namespace boost
+{
+namespace composite_storage
+{
+ template
+ < typename Index
+ >
+struct enum_base
+;
+ template
+ < typename Type
+ , Type Valu
+ >
+struct enum_base
+ < mpl::integral_c<Type,Valu>
+ >
+{
+ typedef
+ int
+ type
+ ;
+};
+}//exit composite_storage namespace
+}//exit boost namespace
+#endif
Added: sandbox/variadic_templates/boost/composite_storage/functor_indexed.hpp
==============================================================================
--- (empty file)
+++ sandbox/variadic_templates/boost/composite_storage/functor_indexed.hpp 2010-06-25 14:10:29 EDT (Fri, 25 Jun 2010)
@@ -0,0 +1,193 @@
+//
+#ifndef BOOST_COMPOSITE_STORAGE_FUNCTOR_INDEXED_HPP_INCLUDED
+#define BOOST_COMPOSITE_STORAGE_FUNCTOR_INDEXED_HPP_INCLUDED
+//[switch #includes
+// These are from:
+//
+// http://svn.boost.org/svn/boost/sandbox/switch/
+//
+ #include <boost/control/switch.hpp>
+ #include <boost/control/case.hpp>
+//]switch #includes
+#include <boost/assert.hpp>
+#include <boost/type_traits/remove_cv.hpp>
+
+namespace boost
+{
+namespace composite_storage
+{
+namespace functor_indexed
+// This namespace defines support templates
+// for use of "Index Functors" taking only index arguments.
+// A "Index Functor" is a functor with the
+// "Index Functor Interface":
+//
+// IndexFunctor::result_type IndexFunctor::operator()
+// ( mpl::integral_c<IndexType,IndexValu> case_c )
+//
+// where:
+//
+// IndexFunctor is an Index Functor.
+// typedef IndexFunctor::cases::value_type IndexType;
+// IndexType IndexValu;
+//
+// the case_c argument above is called
+// "case argument"
+// below.
+//
+{
+
+//The following modified from:
+// http://svn.boost.org/svn/boost/sandbox/switch/libs/switch/example/apply_visitor.cpp
+//As it was on 2009-12-03.1238 CST
+//
+//The comments here starting with //[functor_indexed
+//correspond to the comments in apply_visitor.cpp starting with //[apply_visitor
+//
+//[functor_indexed_implementation
+//
+// bring switch_ and case_ into scope.
+using namespace boost::control;
+
+// One of the cases should always be selected. If the
+// the default is executed it must be an error.
+template<class R>
+struct never_called
+{
+ template<class Int>
+ R operator()(Int)
+ {
+ BOOST_ASSERT(!"this function should never be called.");
+ }
+};
+
+ template
+ < class Visitor
+ //functor with signature (case_c,Component) -> Visitor::result_type
+ //where:
+ // case_c (see below).
+ // component is some component of Variant.
+ //
+ , class Variant
+ // Abstractly, a "dependent index pair", IOW, like std::pair<Key,Value>,
+ // except the type of Value depends on the value of Key part of the pair.
+ // Also Key is of type like case_c below.
+ //
+ // The possible values of Value are called the Components of Variant.
+ >
+struct visitor_variant
+/**@brief
+ * Adapts the Visitor functor to the
+ * Index Functor Interface.
+ */
+{
+ public:
+ typedef
+ typename Visitor::cases
+ cases
+ ;
+ typedef
+ typename cases::value_type
+ case_type
+ ;
+ typedef
+ typename Visitor::result_type
+ result_type
+ ;
+ visitor_variant( Visitor& visitor, Variant& variant)
+ : visitor_(visitor)
+ , variant_(variant)
+ {}
+ template<case_type CaseValu>
+ result_type
+ operator()
+ ( mpl::integral_c<case_type,CaseValu> case_c
+ )
+ {
+ typedef
+ typename Variant::index_type
+ index_type
+ ;
+ return
+ visitor_
+ ( case_c //pass index to visitor
+ , *(variant_.template project<index_type(CaseValu)>())//pass component to visitor
+ );
+ }
+ private:
+ Visitor& visitor_;
+ Variant& variant_;
+};
+
+ template
+ < class IndexFunctor //an Index Functor (see above).
+ >
+ struct
+apply_static
+{
+ typedef
+ typename remove_cv<IndexFunctor>::type
+ index_functor
+ ;
+ typedef
+ typename index_functor::result_type
+ result_type
+ ;
+ typedef
+ typename index_functor::cases
+ cases
+ ;
+ static
+ result_type
+ _
+ ( IndexFunctor& index_functor
+ , typename index_functor::cases::value_type a_case
+ )
+ {
+ never_called<result_type>
+ default_
+ ;
+ return
+ switch_<result_type>(a_case, case_<cases>(index_functor), default_);
+ }
+};
+
+ template
+ < class IndexFunctor //an Index Functor (see above).
+ >
+ typename IndexFunctor::result_type
+apply
+ ( IndexFunctor& index_functor
+ , typename IndexFunctor::cases::value_type a_case
+ )
+{
+ return apply_static<IndexFunctor>::_( index_functor, a_case);
+};
+
+//]functor_indexed_implementation
+
+ template
+ < typename Layout
+ , typename Case0=typename Layout::index_undefined
+ >
+struct layout_visitor
+{
+ typedef
+ typename Case0::value_type
+ case_type
+ ;
+ typedef
+ mpl::range_c
+ < case_type
+ , Case0::value
+ , Layout::index_end::value
+ >
+ cases
+ ;
+};
+
+}//exit namespace functor_indexed
+
+}//exit composite_storage namespace
+}//exit boost namespace
+#endif
Added: sandbox/variadic_templates/boost/composite_storage/special_components.hpp
==============================================================================
--- (empty file)
+++ sandbox/variadic_templates/boost/composite_storage/special_components.hpp 2010-06-25 14:10:29 EDT (Fri, 25 Jun 2010)
@@ -0,0 +1,42 @@
+//components treated "specially" in a composite.
+#ifndef BOOST_COMPOSITE_STORAGE_SPECIAL_COMPONENTS_HPP_INCLUDED
+#define BOOST_COMPOSITE_STORAGE_SPECIAL_COMPONENTS_HPP_INCLUDED
+
+namespace boost
+{
+namespace composite_storage
+{
+namespace special_components
+{
+ enum special_id
+ { nothing_id //signifies error, something like haskell's Nothing.
+ , empty_id //signifies empty class.
+ };
+ template<special_id Id>
+ struct special_type
+ {
+ static
+ special_type*
+ _(void)
+ {
+ static special_type a;
+ return &a;
+ }
+ special_type(void)
+ {}
+ special_type(special_type const&)
+ {}
+ void operator=(special_type const&)
+ {}
+ bool operator==(special_type const&)const
+ {
+ return true;
+ }
+ };
+ typedef special_type<empty_id> empty;
+ typedef special_type<nothing_id> nothing;
+
+}//exit special_components namespace
+}//exit composite_storage namespace
+}//exit boost namespace
+#endif
Added: sandbox/variadic_templates/boost/composite_storage/tags.hpp
==============================================================================
--- (empty file)
+++ sandbox/variadic_templates/boost/composite_storage/tags.hpp 2010-06-25 14:10:29 EDT (Fri, 25 Jun 2010)
@@ -0,0 +1,25 @@
+//tags for various types of composites.
+#ifndef BOOST_COMPOSITE_STORAGE_TAGS_HPP_INCLUDED
+#define BOOST_COMPOSITE_STORAGE_TAGS_HPP_INCLUDED
+
+namespace boost
+{
+namespace composite_storage
+{
+namespace tags
+{
+ struct one_of_maybe
+ //composite contains an instance of 'one of' template arguments, *maybe*.
+ //This composite is like haskell's Maybe except there's more than one
+ //optional value.
+ ;
+ struct all_of_aligned
+ //composite contains instances of 'all of' template arguments, properly 'aligned'.
+ ;
+ struct all_of_packed
+ //composite contains instances of 'all of' template arguments, 'packed' together.
+ ;
+}//exit tags namespace
+}//exit composite_storage namespace
+}//exit boost namespace
+#endif