382 lines
16 KiB
C++
382 lines
16 KiB
C++
|
/*=============================================================================
|
||
|
|
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)
|
||
|
|
=============================================================================*/
|
||
|
|
#ifndef BOOST_SPIRIT_QI_DETAIL_PASS_CONTAINER_HPP
|
||
|
|
#define BOOST_SPIRIT_QI_DETAIL_PASS_CONTAINER_HPP
|
||
|
|
|
||
|
|
#if defined(_MSC_VER)
|
||
|
|
#pragma once
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include <boost/spirit/home/qi/detail/attributes.hpp>
|
||
|
|
#include <boost/spirit/home/support/container.hpp>
|
||
|
|
#include <boost/spirit/home/support/handles_container.hpp>
|
||
|
|
#include <boost/type_traits/is_base_of.hpp>
|
||
|
|
#include <boost/type_traits/is_convertible.hpp>
|
||
|
|
#include <boost/mpl/bool.hpp>
|
||
|
|
#include <boost/mpl/and.hpp>
|
||
|
|
#include <boost/mpl/or.hpp>
|
||
|
|
#include <boost/preprocessor/cat.hpp>
|
||
|
|
#include <boost/preprocessor/repetition/repeat.hpp>
|
||
|
|
|
||
|
|
namespace boost { namespace spirit { namespace qi { namespace detail
|
||
|
|
{
|
||
|
|
// Helper meta-function allowing to evaluate weak substitutability and
|
||
|
|
// negate the result if the predicate (Sequence) is not true
|
||
|
|
template <typename Sequence, typename Attribute, typename ValueType>
|
||
|
|
struct negate_weak_substitute_if_not
|
||
|
|
: mpl::if_<
|
||
|
|
Sequence
|
||
|
|
, typename traits::is_weak_substitute<Attribute, ValueType>::type
|
||
|
|
, typename mpl::not_<
|
||
|
|
traits::is_weak_substitute<Attribute, ValueType>
|
||
|
|
>::type>
|
||
|
|
{};
|
||
|
|
|
||
|
|
// pass_through_container: utility to check decide whether a provided
|
||
|
|
// container attribute needs to be passed through to the current component
|
||
|
|
// or of we need to split the container by passing along instances of its
|
||
|
|
// value type
|
||
|
|
|
||
|
|
// if the expected attribute of the current component is neither a Fusion
|
||
|
|
// sequence nor a container, we will pass through the provided container
|
||
|
|
// only if its value type is not compatible with the component
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence, typename Enable = void>
|
||
|
|
struct pass_through_container_base
|
||
|
|
: negate_weak_substitute_if_not<Sequence, Attribute, ValueType>
|
||
|
|
{};
|
||
|
|
|
||
|
|
// Specialization for fusion sequences, in this case we check whether all
|
||
|
|
// the types in the sequence are convertible to the lhs attribute.
|
||
|
|
//
|
||
|
|
// We return false if the rhs attribute itself is a fusion sequence, which
|
||
|
|
// is compatible with the LHS sequence (we want to pass through this
|
||
|
|
// attribute without it being split apart).
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence = mpl::true_>
|
||
|
|
struct not_compatible_element
|
||
|
|
: mpl::and_<
|
||
|
|
negate_weak_substitute_if_not<Sequence, Attribute, Container>
|
||
|
|
, negate_weak_substitute_if_not<Sequence, Attribute, ValueType> >
|
||
|
|
{};
|
||
|
|
|
||
|
|
// If the value type of the container is not a Fusion sequence, we pass
|
||
|
|
// through the container if each of the elements of the Attribute
|
||
|
|
// sequence is compatible with either the container or its value type.
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence
|
||
|
|
, bool IsSequence = fusion::traits::is_sequence<ValueType>::value>
|
||
|
|
struct pass_through_container_fusion_sequence
|
||
|
|
{
|
||
|
|
typedef typename mpl::find_if<
|
||
|
|
Attribute, not_compatible_element<Container, ValueType, mpl::_1>
|
||
|
|
>::type iter;
|
||
|
|
typedef typename mpl::end<Attribute>::type end;
|
||
|
|
|
||
|
|
typedef typename is_same<iter, end>::type type;
|
||
|
|
};
|
||
|
|
|
||
|
|
// If both, the Attribute and the value type of the provided container
|
||
|
|
// are Fusion sequences, we pass the container only if the two
|
||
|
|
// sequences are not compatible.
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container_fusion_sequence<
|
||
|
|
Container, ValueType, Attribute, Sequence, true>
|
||
|
|
{
|
||
|
|
typedef typename mpl::find_if<
|
||
|
|
Attribute
|
||
|
|
, not_compatible_element<Container, ValueType, mpl::_1, Sequence>
|
||
|
|
>::type iter;
|
||
|
|
typedef typename mpl::end<Attribute>::type end;
|
||
|
|
|
||
|
|
typedef typename is_same<iter, end>::type type;
|
||
|
|
};
|
||
|
|
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container_base<Container, ValueType, Attribute
|
||
|
|
, Sequence
|
||
|
|
, typename enable_if<fusion::traits::is_sequence<Attribute> >::type>
|
||
|
|
: pass_through_container_fusion_sequence<
|
||
|
|
Container, ValueType, Attribute, Sequence>
|
||
|
|
{};
|
||
|
|
|
||
|
|
// Specialization for containers
|
||
|
|
//
|
||
|
|
// If the value type of the attribute of the current component is not
|
||
|
|
// a Fusion sequence, we have to pass through the provided container if
|
||
|
|
// both are compatible.
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence, typename AttributeValueType
|
||
|
|
, bool IsSequence = fusion::traits::is_sequence<AttributeValueType>::value>
|
||
|
|
struct pass_through_container_container
|
||
|
|
: mpl::or_<
|
||
|
|
traits::is_weak_substitute<Attribute, Container>
|
||
|
|
, traits::is_weak_substitute<AttributeValueType, Container> >
|
||
|
|
{};
|
||
|
|
|
||
|
|
// If the value type of the exposed container attribute is a Fusion
|
||
|
|
// sequence, we use the already existing logic for those.
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence, typename AttributeValueType>
|
||
|
|
struct pass_through_container_container<
|
||
|
|
Container, ValueType, Attribute, Sequence, AttributeValueType, true>
|
||
|
|
: pass_through_container_fusion_sequence<
|
||
|
|
Container, ValueType, AttributeValueType, Sequence>
|
||
|
|
{};
|
||
|
|
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container_base<
|
||
|
|
Container, ValueType, Attribute, Sequence
|
||
|
|
, typename enable_if<traits::is_container<Attribute> >::type>
|
||
|
|
: detail::pass_through_container_container<
|
||
|
|
Container, ValueType, Attribute, Sequence
|
||
|
|
, typename traits::container_value<Attribute>::type>
|
||
|
|
{};
|
||
|
|
|
||
|
|
// Specialization for exposed optional attributes
|
||
|
|
//
|
||
|
|
// If the type embedded in the exposed optional is not a Fusion
|
||
|
|
// sequence we pass through the container attribute if it is compatible
|
||
|
|
// either to the optionals embedded type or to the containers value
|
||
|
|
// type.
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence
|
||
|
|
, bool IsSequence = fusion::traits::is_sequence<Attribute>::value>
|
||
|
|
struct pass_through_container_optional
|
||
|
|
: mpl::or_<
|
||
|
|
traits::is_weak_substitute<Attribute, Container>
|
||
|
|
, traits::is_weak_substitute<Attribute, ValueType> >
|
||
|
|
{};
|
||
|
|
|
||
|
|
// If the embedded type of the exposed optional attribute is a Fusion
|
||
|
|
// sequence, we use the already existing logic for those.
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container_optional<
|
||
|
|
Container, ValueType, Attribute, Sequence, true>
|
||
|
|
: pass_through_container_fusion_sequence<
|
||
|
|
Container, ValueType, Attribute, Sequence>
|
||
|
|
{};
|
||
|
|
|
||
|
|
///////////////////////////////////////////////////////////////////////////
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container
|
||
|
|
: pass_through_container_base<Container, ValueType, Attribute, Sequence>
|
||
|
|
{};
|
||
|
|
|
||
|
|
// Handle optional attributes
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container<
|
||
|
|
Container, ValueType, boost::optional<Attribute>, Sequence>
|
||
|
|
: pass_through_container_optional<
|
||
|
|
Container, ValueType, Attribute, Sequence>
|
||
|
|
{};
|
||
|
|
|
||
|
|
// If both, the containers value type and the exposed attribute type are
|
||
|
|
// optionals we are allowed to pass through the container only if the
|
||
|
|
// embedded types of those optionals are not compatible.
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container<
|
||
|
|
Container, boost::optional<ValueType>, boost::optional<Attribute>
|
||
|
|
, Sequence>
|
||
|
|
: mpl::not_<traits::is_weak_substitute<Attribute, ValueType> >
|
||
|
|
{};
|
||
|
|
|
||
|
|
// Specialization for exposed variant attributes
|
||
|
|
//
|
||
|
|
// We pass through the container attribute if at least one of the embedded
|
||
|
|
// types in the variant requires to pass through the attribute
|
||
|
|
|
||
|
|
#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
|
||
|
|
template <typename Container, typename ValueType, typename Sequence
|
||
|
|
, typename T>
|
||
|
|
struct pass_through_container<Container, ValueType, boost::variant<T>
|
||
|
|
, Sequence>
|
||
|
|
: pass_through_container<Container, ValueType, T, Sequence>
|
||
|
|
{};
|
||
|
|
|
||
|
|
template <typename Container, typename ValueType, typename Sequence
|
||
|
|
, typename T0, typename ...TN>
|
||
|
|
struct pass_through_container<Container, ValueType
|
||
|
|
, boost::variant<T0, TN...>, Sequence>
|
||
|
|
: mpl::bool_<pass_through_container<
|
||
|
|
Container, ValueType, T0, Sequence
|
||
|
|
>::type::value || pass_through_container<
|
||
|
|
Container, ValueType, boost::variant<TN...>, Sequence
|
||
|
|
>::type::value>
|
||
|
|
{};
|
||
|
|
#else
|
||
|
|
#define BOOST_SPIRIT_PASS_THROUGH_CONTAINER(z, N, _) \
|
||
|
|
pass_through_container<Container, ValueType, \
|
||
|
|
BOOST_PP_CAT(T, N), Sequence>::type::value || \
|
||
|
|
/***/
|
||
|
|
|
||
|
|
// make sure unused variant parameters do not affect the outcome
|
||
|
|
template <typename Container, typename ValueType, typename Sequence>
|
||
|
|
struct pass_through_container<Container, ValueType
|
||
|
|
, boost::detail::variant::void_, Sequence>
|
||
|
|
: mpl::false_
|
||
|
|
{};
|
||
|
|
|
||
|
|
template <typename Container, typename ValueType, typename Sequence
|
||
|
|
, BOOST_VARIANT_ENUM_PARAMS(typename T)>
|
||
|
|
struct pass_through_container<Container, ValueType
|
||
|
|
, boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>, Sequence>
|
||
|
|
: mpl::bool_<BOOST_PP_REPEAT(BOOST_VARIANT_LIMIT_TYPES
|
||
|
|
, BOOST_SPIRIT_PASS_THROUGH_CONTAINER, _) false>
|
||
|
|
{};
|
||
|
|
|
||
|
|
#undef BOOST_SPIRIT_PASS_THROUGH_CONTAINER
|
||
|
|
#endif
|
||
|
|
}}}}
|
||
|
|
|
||
|
|
///////////////////////////////////////////////////////////////////////////////
|
||
|
|
namespace boost { namespace spirit { namespace traits
|
||
|
|
{
|
||
|
|
///////////////////////////////////////////////////////////////////////////
|
||
|
|
// forwarding customization point for domain qi::domain
|
||
|
|
template <typename Container, typename ValueType, typename Attribute
|
||
|
|
, typename Sequence>
|
||
|
|
struct pass_through_container<
|
||
|
|
Container, ValueType, Attribute, Sequence, qi::domain>
|
||
|
|
: qi::detail::pass_through_container<
|
||
|
|
Container, ValueType, Attribute, Sequence>
|
||
|
|
{};
|
||
|
|
}}}
|
||
|
|
|
||
|
|
namespace boost { namespace spirit { namespace qi { namespace detail
|
||
|
|
{
|
||
|
|
///////////////////////////////////////////////////////////////////////////
|
||
|
|
// This function handles the case where the attribute (Attr) given
|
||
|
|
// the sequence is an STL container. This is a wrapper around F.
|
||
|
|
// The function F does the actual parsing.
|
||
|
|
template <typename F, typename Attr, typename Sequence>
|
||
|
|
struct pass_container
|
||
|
|
{
|
||
|
|
typedef typename F::context_type context_type;
|
||
|
|
typedef typename F::iterator_type iterator_type;
|
||
|
|
|
||
|
|
pass_container(F const& f_, Attr& attr_)
|
||
|
|
: f(f_), attr(attr_) {}
|
||
|
|
|
||
|
|
// this is for the case when the current element exposes an attribute
|
||
|
|
// which is pushed back onto the container
|
||
|
|
template <typename Component>
|
||
|
|
bool dispatch_container(Component const& component, mpl::false_) const
|
||
|
|
{
|
||
|
|
// synthesized attribute needs to be default constructed
|
||
|
|
typename traits::container_value<Attr>::type val =
|
||
|
|
typename traits::container_value<Attr>::type();
|
||
|
|
|
||
|
|
iterator_type save = f.first;
|
||
|
|
bool r = f(component, val);
|
||
|
|
if (!r)
|
||
|
|
{
|
||
|
|
// push the parsed value into our attribute
|
||
|
|
r = !traits::push_back(attr, val);
|
||
|
|
if (r)
|
||
|
|
f.first = save;
|
||
|
|
}
|
||
|
|
return r;
|
||
|
|
}
|
||
|
|
|
||
|
|
// this is for the case when the current element is able to handle an
|
||
|
|
// attribute which is a container itself, this element will push its
|
||
|
|
// data directly into the attribute container
|
||
|
|
template <typename Component>
|
||
|
|
bool dispatch_container(Component const& component, mpl::true_) const
|
||
|
|
{
|
||
|
|
return f(component, attr);
|
||
|
|
}
|
||
|
|
|
||
|
|
///////////////////////////////////////////////////////////////////////
|
||
|
|
// this is for the case when the current element doesn't expect an
|
||
|
|
// attribute
|
||
|
|
template <typename Component>
|
||
|
|
bool dispatch_attribute(Component const& component, mpl::false_) const
|
||
|
|
{
|
||
|
|
return f(component, unused);
|
||
|
|
}
|
||
|
|
|
||
|
|
// the current element expects an attribute
|
||
|
|
template <typename Component>
|
||
|
|
bool dispatch_attribute(Component const& component, mpl::true_) const
|
||
|
|
{
|
||
|
|
typedef typename traits::container_value<Attr>::type value_type;
|
||
|
|
typedef typename traits::attribute_of<
|
||
|
|
Component, context_type, iterator_type>::type
|
||
|
|
rhs_attribute;
|
||
|
|
|
||
|
|
// this predicate detects, whether the attribute of the current
|
||
|
|
// element is a substitute for the value type of the container
|
||
|
|
// attribute
|
||
|
|
typedef mpl::and_<
|
||
|
|
traits::handles_container<
|
||
|
|
Component, Attr, context_type, iterator_type>
|
||
|
|
, traits::pass_through_container<
|
||
|
|
Attr, value_type, rhs_attribute, Sequence, qi::domain>
|
||
|
|
> predicate;
|
||
|
|
|
||
|
|
return dispatch_container(component, predicate());
|
||
|
|
}
|
||
|
|
|
||
|
|
// Dispatches to dispatch_main depending on the attribute type
|
||
|
|
// of the Component
|
||
|
|
template <typename Component>
|
||
|
|
bool operator()(Component const& component) const
|
||
|
|
{
|
||
|
|
// we need to dispatch depending on the type of the attribute
|
||
|
|
// of the current element (component). If this is has no attribute
|
||
|
|
// we shouldn't pass an attribute at all.
|
||
|
|
typedef typename traits::not_is_unused<
|
||
|
|
typename traits::attribute_of<
|
||
|
|
Component, context_type, iterator_type
|
||
|
|
>::type
|
||
|
|
>::type predicate;
|
||
|
|
|
||
|
|
// ensure the attribute is actually a container type
|
||
|
|
traits::make_container(attr);
|
||
|
|
|
||
|
|
return dispatch_attribute(component, predicate());
|
||
|
|
}
|
||
|
|
|
||
|
|
F f;
|
||
|
|
Attr& attr;
|
||
|
|
|
||
|
|
// silence MSVC warning C4512: assignment operator could not be generated
|
||
|
|
BOOST_DELETED_FUNCTION(pass_container& operator= (pass_container const&))
|
||
|
|
};
|
||
|
|
|
||
|
|
///////////////////////////////////////////////////////////////////////////
|
||
|
|
// Utility function to make a pass_container for container components
|
||
|
|
// (kleene, list, plus, repeat)
|
||
|
|
template <typename F, typename Attr>
|
||
|
|
inline pass_container<F, Attr, mpl::false_>
|
||
|
|
make_pass_container(F const& f, Attr& attr)
|
||
|
|
{
|
||
|
|
return pass_container<F, Attr, mpl::false_>(f, attr);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Utility function to make a pass_container for sequences
|
||
|
|
template <typename F, typename Attr>
|
||
|
|
inline pass_container<F, Attr, mpl::true_>
|
||
|
|
make_sequence_pass_container(F const& f, Attr& attr)
|
||
|
|
{
|
||
|
|
return pass_container<F, Attr, mpl::true_>(f, attr);
|
||
|
|
}
|
||
|
|
}}}}
|
||
|
|
|
||
|
|
#endif
|
||
|
|
|