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Boost-Commit : |
From: eric_at_[hidden]
Date: 2008-05-17 12:19:50
Author: eric_niebler
Date: 2008-05-17 12:19:49 EDT (Sat, 17 May 2008)
New Revision: 45455
URL: http://svn.boost.org/trac/boost/changeset/45455
Log:
add switch statement
Added:
branches/proto/v4/boost/phoenix/statement/switch.hpp (contents, props changed)
Text files modified:
branches/proto/v4/boost/phoenix/core/actor.hpp | 42 ++++++++++++++++++++--------------------
branches/proto/v4/boost/phoenix/statement.hpp | 2
2 files changed, 22 insertions(+), 22 deletions(-)
Modified: branches/proto/v4/boost/phoenix/core/actor.hpp
==============================================================================
--- branches/proto/v4/boost/phoenix/core/actor.hpp (original)
+++ branches/proto/v4/boost/phoenix/core/actor.hpp 2008-05-17 12:19:49 EDT (Sat, 17 May 2008)
@@ -62,31 +62,31 @@
using actorns_::actor;
- namespace detail
+ ////////////////////////////////////////////////////////////////////////////////////////
+ // True when a lambda expression can be applied with no arguments and
+ // without an active exception object
+ struct is_nullary
+ : proto::switch_<struct is_nullary_cases>
+ {};
+
+ ////////////////////////////////////////////////////////////////////////////////////////
+ struct is_nullary_cases
{
- ////////////////////////////////////////////////////////////////////////////////////////
- // True when a lambda expression can be applied with no arguments and
- // without an active exception object
- struct is_nullary
- : proto::switch_<struct is_nullary_cases>
+ template<typename Tag>
+ struct case_
+ : proto::otherwise<
+ proto::fold<proto::_, mpl::true_(), mpl::and_<proto::_state, is_nullary>()>
+ >
{};
+ };
- ////////////////////////////////////////////////////////////////////////////////////////
- struct is_nullary_cases
- {
- template<typename Tag>
- struct case_
- : proto::otherwise<
- proto::fold<proto::_, mpl::true_(), mpl::and_<proto::_state, is_nullary>()>
- >
- {};
- };
-
- template<>
- struct is_nullary_cases::case_<proto::tag::terminal>
- : proto::otherwise<is_terminal_nullary<proto::_value>()>
- {};
+ template<>
+ struct is_nullary_cases::case_<proto::tag::terminal>
+ : proto::otherwise<is_terminal_nullary<proto::_value>()>
+ {};
+ namespace detail
+ {
////////////////////////////////////////////////////////////////////////////////////////
struct evaluator_cases
{
Modified: branches/proto/v4/boost/phoenix/statement.hpp
==============================================================================
--- branches/proto/v4/boost/phoenix/statement.hpp (original)
+++ branches/proto/v4/boost/phoenix/statement.hpp 2008-05-17 12:19:49 EDT (Sat, 17 May 2008)
@@ -12,7 +12,7 @@
#include <boost/phoenix/statement/for.hpp>
#include <boost/phoenix/statement/if.hpp>
//#include <boost/phoenix/statement/sequence.hpp>
-//#include <boost/phoenix/statement/switch.hpp>
+#include <boost/phoenix/statement/switch.hpp>
#include <boost/phoenix/statement/while.hpp>
//#include <boost/phoenix/statement/throw.hpp>
//#include <boost/phoenix/statement/try_catch.hpp>
Added: branches/proto/v4/boost/phoenix/statement/switch.hpp
==============================================================================
--- (empty file)
+++ branches/proto/v4/boost/phoenix/statement/switch.hpp 2008-05-17 12:19:49 EDT (Sat, 17 May 2008)
@@ -0,0 +1,283 @@
+#ifndef BOOST_PP_IS_ITERATING
+ /*=============================================================================
+ Copyright (c) 2001-2007 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)
+ ==============================================================================*/
+ #ifndef BOOST_PHOENIX_SWITCH_HPP_EAN_2008_05_10
+ #define BOOST_PHOENIX_SWITCH_HPP_EAN_2008_05_10
+
+ #include <boost/ref.hpp>
+ #include <boost/mpl/int.hpp>
+ #include <boost/mpl/assert.hpp>
+ #include <boost/mpl/equal_to.hpp>
+ #include <boost/mpl/next_prior.hpp>
+ #include <boost/preprocessor.hpp>
+ #include <boost/proto/proto.hpp>
+ #include <boost/phoenix/core/actor.hpp>
+ #include <boost/fusion/include/as_vector.hpp>
+
+ #ifdef _MSC_VER
+ # pragma warning(push)
+ # pragma warning(disable: 4065) // switch statement contains 'default' but no 'case' labels
+ #endif
+
+ namespace boost { namespace phoenix
+ {
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ namespace tag
+ {
+ struct switch_ {};
+ struct default_ {};
+ template<int Label>
+ struct case_ { BOOST_STATIC_CONSTANT(int, label = Label); };
+ }
+
+ namespace detail
+ {
+ ////////////////////////////////////////////////////////////////////////////////////////
+ template<typename Cond>
+ struct switch_generator
+ {
+ explicit switch_generator(Cond const &c)
+ : cond(c)
+ {}
+
+ template<typename Body>
+ typename proto::result_of::make_expr<
+ tag::switch_
+ , domain
+ , Cond const &
+ , Body const &
+ >::type const
+ operator[](Body const &body) const
+ {
+ return proto::implicit_expr(this->cond, body);
+ }
+
+ private:
+ switch_generator &operator =(switch_generator const &);
+ Cond const &cond;
+ };
+
+ // Define the grammar for valid switch statements
+ struct Case
+ : proto::switch_<struct CaseCases>
+ {};
+
+ struct CaseCases
+ {
+ template<typename Tag>
+ struct case_
+ : proto::not_<proto::_>
+ {};
+
+ template<int Label>
+ struct case_<tag::case_<Label> >
+ : proto::unary_expr<proto::_, evaluator>
+ {};
+ };
+
+ struct Default
+ : proto::unary_expr<tag::default_, evaluator>
+ {};
+
+ struct CasesNoDefault
+ : proto::or_<
+ Case
+ , proto::comma<CasesNoDefault, Case>
+ >
+ {};
+
+ struct CasesWithDefault
+ : proto::or_<
+ Default
+ , proto::comma<CasesNoDefault, Default>
+ >
+ {};
+
+ struct Switch
+ : proto::binary_expr<
+ tag::switch_
+ , evaluator
+ , proto::or_<CasesNoDefault, CasesWithDefault>
+ >
+ {};
+
+ #define BOOST_PP_ITERATION_PARAMS_1 (3, (0, PHOENIX_LIMIT, <boost/phoenix/statement/switch.hpp>))
+ #include BOOST_PP_ITERATE()
+
+ ////////////////////////////////////////////////////////////////////////////////////////
+ // Proto transform that evaluates switch(condition)[ case_<0>(expr), case_<1>(expr), ... ]
+ struct switch_evaluator
+ : proto::transform<switch_evaluator>
+ {
+ template<typename Expr, typename State, typename Data>
+ struct impl
+ : proto::transform_impl<Expr, State, Data>
+ {
+ typedef void result_type;
+
+ void operator()(
+ typename impl::expr_param expr
+ , typename impl::state_param state
+ , typename impl::data_param data
+ ) const
+ {
+ detail::do_switch(
+ expr.proto_base().child0, state, data
+ , expr.proto_base().child1.proto_base()
+ );
+ }
+ };
+ };
+
+ }
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<typename Expr>
+ detail::switch_generator<Expr> const
+ switch_(Expr const &expr)
+ {
+ return detail::switch_generator<Expr>(expr);
+ }
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<int Label, typename Expr>
+ typename proto::result_of::make_expr<
+ tag::case_<Label>
+ , detail::domain
+ , Expr const &
+ >::type const
+ case_(Expr const &expr)
+ {
+ return proto::implicit_expr(expr);
+ }
+
+ template<typename Expr>
+ typename proto::result_of::make_expr<
+ tag::default_
+ , detail::domain
+ , Expr const &
+ >::type const
+ default_(Expr const &expr)
+ {
+ return proto::implicit_expr(expr);
+ }
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<>
+ struct extension<tag::switch_, void>
+ : proto::when<
+ detail::Switch
+ , detail::switch_evaluator
+ >
+ {};
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<int Label>
+ struct is_nullary_cases::case_<tag::case_<Label> >
+ : proto::otherwise<mpl::false_()>
+ {};
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<>
+ struct is_nullary_cases::case_<tag::default_>
+ : proto::otherwise<mpl::false_()>
+ {};
+
+ }}
+
+ #ifdef _MSC_VER
+ # pragma warning(pop)
+ #endif
+
+ #endif
+
+#else
+
+ #define N BOOST_PP_ITERATION()
+
+ #define M0(Z, N, DATA) \
+ proto::expr<tag::case_<BOOST_PP_CAT(L, N)>, BOOST_PP_CAT(A, N), 1> const &BOOST_PP_CAT(a, N)\
+ /**/
+
+ #define M1(Z, N, DATA) \
+ case BOOST_PP_CAT(L, N): \
+ evaluator()(BOOST_PP_CAT(a, N).child0, state, data); \
+ break; \
+ /**/
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<
+ typename Expr, typename State, typename Data
+ , typename A0
+ BOOST_PP_COMMA_IF(N)
+ BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PP_INC(N), typename A)
+ >
+ void do_switch(
+ Expr &expr, State &state, Data &data
+ , proto::expr<proto::tag::comma, A0, 2> const &a0
+ BOOST_PP_COMMA_IF(N)
+ BOOST_PP_ENUM_SHIFTED_BINARY_PARAMS(BOOST_PP_INC(N), A, const &a)
+ )
+ {
+ // Fan out the arguments
+ detail::do_switch(
+ expr, state, data
+ , a0.child0.proto_base()
+ , a0.child1.proto_base()
+ BOOST_PP_COMMA_IF(N)
+ BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PP_INC(N), a)
+ );
+ }
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<
+ typename Expr, typename State, typename Data
+ BOOST_PP_ENUM_TRAILING_PARAMS(N, int L)
+ BOOST_PP_ENUM_TRAILING_PARAMS(N, typename A)
+ , int BOOST_PP_CAT(L, N), typename BOOST_PP_CAT(A, N)
+ >
+ void do_switch(
+ Expr &expr, State &state, Data &data
+ BOOST_PP_ENUM_TRAILING(N, M0, ~)
+ , proto::expr<tag::case_<BOOST_PP_CAT(L, N)>, BOOST_PP_CAT(A, N), 1> const &BOOST_PP_CAT(a, N)
+ )
+ {
+ switch(evaluator()(expr, state, data))
+ {
+ BOOST_PP_REPEAT(BOOST_PP_INC(N), M1, ~)
+ default:;
+ }
+ }
+
+ ////////////////////////////////////////////////////////////////////////////////////////////
+ template<
+ typename Expr, typename State, typename Data
+ BOOST_PP_ENUM_TRAILING_PARAMS(N, int L)
+ BOOST_PP_ENUM_TRAILING_PARAMS(N, typename A)
+ , typename BOOST_PP_CAT(A, N)
+ >
+ void do_switch(
+ Expr &expr, State &state, Data &data
+ BOOST_PP_ENUM_TRAILING(N, M0, ~)
+ , proto::expr<tag::default_, BOOST_PP_CAT(A, N), 1> const &BOOST_PP_CAT(a, N)
+ )
+ {
+ switch(evaluator()(expr, state, data))
+ {
+ BOOST_PP_REPEAT(N, M1, ~)
+ default:
+ evaluator()(BOOST_PP_CAT(a, N).child0, state, data);
+ break;
+ }
+ }
+
+ #undef M0
+ #undef M1
+
+ #undef N
+
+#endif
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