Subject: [Boost-commit] svn:boost r50709 - in trunk/boost/flyweight: . detail
From: joaquin_at_[hidden]
Date: 2009-01-21 14:52:03
Author: joaquin
Date: 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
New Revision: 50709
URL: http://svn.boost.org/trac/boost/changeset/50709
Log:
reverted rev. 50283
prevented assoc_container_factory_class<Container> from instantiating Container when this type is an MPL placeholder expression
Added:
trunk/boost/flyweight/detail/is_placeholder_expr.hpp (contents, props changed)
trunk/boost/flyweight/detail/nested_xxx_if_not_ph.hpp (contents, props changed)
Text files modified:
trunk/boost/flyweight/assoc_container_factory.hpp | 35 +++++++++++++++++++++--------------
trunk/boost/flyweight/hashed_factory.hpp | 16 +---------------
trunk/boost/flyweight/intermodule_holder.hpp | 12 +-----------
trunk/boost/flyweight/set_factory.hpp | 16 +---------------
trunk/boost/flyweight/static_holder.hpp | 12 +-----------
5 files changed, 25 insertions(+), 66 deletions(-)
Modified: trunk/boost/flyweight/assoc_container_factory.hpp
==============================================================================
--- trunk/boost/flyweight/assoc_container_factory.hpp (original)
+++ trunk/boost/flyweight/assoc_container_factory.hpp 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
@@ -1,4 +1,4 @@
-/* Copyright 2006-2008 Joaquin M Lopez Munoz.
+/* Copyright 2006-2009 Joaquin M Lopez Munoz.
* 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)
@@ -15,10 +15,16 @@
#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
#include <boost/flyweight/assoc_container_factory_fwd.hpp>
+#include <boost/flyweight/detail/nested_xxx_if_not_ph.hpp>
#include <boost/flyweight/factory_tag.hpp>
#include <boost/mpl/apply.hpp>
#include <boost/mpl/aux_/lambda_support.hpp>
+namespace boost{namespace flyweights{namespace detail{
+BOOST_FLYWEIGHT_NESTED_XXX_IF_NOT_PLACEHOLDER_EXPRESSION_DEF(iterator);
+BOOST_FLYWEIGHT_NESTED_XXX_IF_NOT_PLACEHOLDER_EXPRESSION_DEF(value_type);
+}}} /* namespace boost::flyweights::detail */
+
/* Factory class using a given associative container.
*/
@@ -30,8 +36,20 @@
class assoc_container_factory_class:public factory_marker
{
public:
- typedef typename Container::iterator handle_type;
- typedef typename Container::value_type entry_type;
+
+ /* When assoc_container_factory_class<Container> is an MPL placeholder
+ * expression, referring to Container::iterator and Container::value_type
+ * force the MPL placeholder expression Container to be instantiated, which
+ * is wasteful and can fail in concept-checked STL implementations.
+ * We protect ourselves against this circumstance.
+ */
+
+ typedef typename detail::nested_iterator_if_not_placeholder_expression<
+ Container
+ >::type handle_type;
+ typedef typename detail::nested_value_type_if_not_placeholder_expression<
+ Container
+ >::type entry_type;
handle_type insert(const entry_type& x)
{
@@ -53,17 +71,6 @@
BOOST_MPL_AUX_LAMBDA_SUPPORT(1,assoc_container_factory_class,(Container))
};
-#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
-/* This is preferred to deriving from factory_marker since checking for
- * derivation forces the instantiation of the specifier, which is not
- * needed when the specifier is a placeholder expression.
- */
-
-template<typename Container>
-struct is_factory<assoc_container_factory_class<Container> >:
- boost::mpl::true_{};
-#endif
-
/* assoc_container_factory_class specifier */
template<
Added: trunk/boost/flyweight/detail/is_placeholder_expr.hpp
==============================================================================
--- (empty file)
+++ trunk/boost/flyweight/detail/is_placeholder_expr.hpp 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
@@ -0,0 +1,65 @@
+/* Copyright 2006-2009 Joaquin M Lopez Munoz.
+ * 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)
+ *
+ * See http://www.boost.org/libs/flyweight for library home page.
+ */
+
+#ifndef BOOST_FLYWEIGHT_DETAIL_IS_PLACEHOLDER_EXPR_HPP
+#define BOOST_FLYWEIGHT_DETAIL_IS_PLACEHOLDER_EXPR_HPP
+
+#if defined(_MSC_VER)&&(_MSC_VER>=1200)
+#pragma once
+#endif
+
+#include <boost/type_traits/is_same.hpp>
+#include <boost/mpl/apply.hpp>
+#include <boost/mpl/aux_/lambda_support.hpp>
+#include <boost/mpl/not.hpp>
+#include <boost/preprocessor/facilities/intercept.hpp>
+#include <boost/preprocessor/repetition/enum_params.hpp>
+
+namespace boost{
+
+namespace flyweights{
+
+namespace detail{
+
+/* is_placeholder_expression<T> indicates whether T is an
+ * MPL placeholder expression.
+ */
+
+template<typename T>
+struct is_placeholder_expression_helper
+{
+ template<
+ BOOST_PP_ENUM_PARAMS(
+ BOOST_MPL_LIMIT_METAFUNCTION_ARITY,typename BOOST_PP_INTERCEPT)
+ >
+ struct apply{
+ typedef int type;
+ };
+
+ BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_placeholder_expression_helper,(T))
+};
+
+template<typename T>
+struct is_placeholder_expression:
+ mpl::not_<is_same<
+ typename mpl::apply<
+ is_placeholder_expression_helper<T>,
+ BOOST_PP_ENUM_PARAMS(
+ BOOST_MPL_LIMIT_METAFUNCTION_ARITY,int BOOST_PP_INTERCEPT)
+ >::type,
+ int
+ > >
+{};
+
+} /* namespace flyweights::detail */
+
+} /* namespace flyweights */
+
+} /* namespace boost */
+
+#endif
Added: trunk/boost/flyweight/detail/nested_xxx_if_not_ph.hpp
==============================================================================
--- (empty file)
+++ trunk/boost/flyweight/detail/nested_xxx_if_not_ph.hpp 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
@@ -0,0 +1,39 @@
+/* Copyright 2006-2009 Joaquin M Lopez Munoz.
+ * 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)
+ *
+ * See http://www.boost.org/libs/flyweight for library home page.
+ */
+
+#ifndef BOOST_FLYWEIGHT_DETAIL_NESTED_XXX_IF_NOT_PH_HPP
+#define BOOST_FLYWEIGHT_DETAIL_NESTED_XXX_IF_NOT_PH_HPP
+
+#if defined(_MSC_VER)&&(_MSC_VER>=1200)
+#pragma once
+#endif
+
+#include <boost/flyweight/detail/is_placeholder_expr.hpp>
+#include <boost/mpl/if.hpp>
+
+/* nested_##name##_if_not_placeholder_expression<T>::type is T::name unless
+ * T is an MPL placeholder expression, in which case it defaults to int.
+ */
+
+#define BOOST_FLYWEIGHT_NESTED_XXX_IF_NOT_PLACEHOLDER_EXPRESSION_DEF(name) \
+struct nested_##name##_if_not_placeholder_expression_helper \
+{ \
+ typedef int name; \
+}; \
+ \
+template<typename T> \
+struct nested_##name##_if_not_placeholder_expression \
+{ \
+ typedef typename boost::mpl::if_< \
+ boost::flyweights::detail::is_placeholder_expression<T>, \
+ nested_##name##_if_not_placeholder_expression_helper, \
+ T \
+ >::type::name type; \
+};
+
+#endif
Modified: trunk/boost/flyweight/hashed_factory.hpp
==============================================================================
--- trunk/boost/flyweight/hashed_factory.hpp (original)
+++ trunk/boost/flyweight/hashed_factory.hpp 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
@@ -1,4 +1,4 @@
-/* Copyright 2006-2008 Joaquin M Lopez Munoz.
+/* Copyright 2006-2009 Joaquin M Lopez Munoz.
* 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)
@@ -88,20 +88,6 @@
5,hashed_factory_class,(Entry,Key,Hash,Pred,Allocator))
};
-#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
-/* This is preferred to deriving from factory_marker since checking for
- * derivation forces the instantiation of the specifier, which is not
- * needed when the specifier is a placeholder expression.
- */
-
-template<
- typename Entry,typename Key,
- typename Hash,typename Pred,typename Allocator
->
-struct is_factory<hashed_factory_class<Entry,Key,Hash,Pred,Allocator> >:
- boost::mpl::true_{};
-#endif
-
/* hashed_factory_class specifier */
template<
Modified: trunk/boost/flyweight/intermodule_holder.hpp
==============================================================================
--- trunk/boost/flyweight/intermodule_holder.hpp (original)
+++ trunk/boost/flyweight/intermodule_holder.hpp 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
@@ -1,4 +1,4 @@
-/* Copyright 2006-2008 Joaquin M Lopez Munoz.
+/* Copyright 2006-2009 Joaquin M Lopez Munoz.
* 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)
@@ -174,16 +174,6 @@
BOOST_MPL_AUX_LAMBDA_SUPPORT(1,intermodule_holder_class,(C))
};
-#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
-/* This is preferred to deriving from holder_marker since checking for
- * derivation forces the instantiation of the specifier, which is not
- * needed when the specifier is a placeholder expression.
- */
-
-template<typename C>
-struct is_holder<intermodule_holder_class<C> >:boost::mpl::true_{};
-#endif
-
/* intermodule_holder_class specifier */
struct intermodule_holder:holder_marker
Modified: trunk/boost/flyweight/set_factory.hpp
==============================================================================
--- trunk/boost/flyweight/set_factory.hpp (original)
+++ trunk/boost/flyweight/set_factory.hpp 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
@@ -1,4 +1,4 @@
-/* Copyright 2006-2008 Joaquin M Lopez Munoz.
+/* Copyright 2006-2009 Joaquin M Lopez Munoz.
* 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)
@@ -56,20 +56,6 @@
4,set_factory_class,(Entry,Key,Compare,Allocator))
};
-#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
-/* This is preferred to deriving from factory_marker since checking for
- * derivation forces the instantiation of the specifier, which is not
- * needed when the specifier is a placeholder expression.
- */
-
-template<
- typename Entry,typename Key,
- typename Compare,typename Allocator
->
-struct is_factory<set_factory_class<Entry,Key,Compare,Allocator> >:
- boost::mpl::true_{};
-#endif
-
/* set_factory_class specifier */
template<
Modified: trunk/boost/flyweight/static_holder.hpp
==============================================================================
--- trunk/boost/flyweight/static_holder.hpp (original)
+++ trunk/boost/flyweight/static_holder.hpp 2009-01-21 14:52:01 EST (Wed, 21 Jan 2009)
@@ -1,4 +1,4 @@
-/* Copyright 2006-2008 Joaquin M Lopez Munoz.
+/* Copyright 2006-2009 Joaquin M Lopez Munoz.
* 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)
@@ -38,16 +38,6 @@
BOOST_MPL_AUX_LAMBDA_SUPPORT(1,static_holder_class,(C))
};
-#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
-/* This is preferred to deriving from holder_marker since checking for
- * derivation forces the instantiation of the specifier, which is not
- * needed when the specifier is a placeholder expression.
- */
-
-template<typename C>
-struct is_holder<static_holder_class<C> >:boost::mpl::true_{};
-#endif
-
/* static_holder_class specifier */
struct static_holder:holder_marker