+++ /dev/null
-// (C) Copyright David Abrahams 2002.
-// (C) Copyright Jeremy Siek 2002.
-// (C) Copyright Thomas Witt 2002.
-// 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_ITERATOR_ADAPTOR_23022003THW_HPP
-#define BOOST_ITERATOR_ADAPTOR_23022003THW_HPP
-
-#include <boost/static_assert.hpp>
-
-#include <boost/core/use_default.hpp>
-
-#include <boost/iterator/iterator_categories.hpp>
-#include <boost/iterator/iterator_facade.hpp>
-#include <boost/iterator/detail/enable_if.hpp>
-
-#include <boost/mpl/and.hpp>
-#include <boost/mpl/not.hpp>
-#include <boost/mpl/or.hpp>
-
-#include <boost/type_traits/is_same.hpp>
-#include <boost/type_traits/is_convertible.hpp>
-
-#ifdef BOOST_ITERATOR_REF_CONSTNESS_KILLS_WRITABILITY
-# include <boost/type_traits/remove_reference.hpp>
-#endif
-
-#include <boost/type_traits/add_reference.hpp>
-#include <boost/iterator/detail/config_def.hpp>
-
-#include <boost/iterator/iterator_traits.hpp>
-
-namespace boost {
-namespace iterators {
-
- // Used as a default template argument internally, merely to
- // indicate "use the default", this can also be passed by users
- // explicitly in order to specify that the default should be used.
- using boost::use_default;
-
-} // namespace iterators
-
-// the incompleteness of use_default causes massive problems for
-// is_convertible (naturally). This workaround is fortunately not
-// needed for vc6/vc7.
-template<class To>
-struct is_convertible<use_default,To>
- : mpl::false_ {};
-
-namespace iterators {
-
- namespace detail
- {
-
- //
- // Result type used in enable_if_convertible meta function.
- // This can be an incomplete type, as only pointers to
- // enable_if_convertible< ... >::type are used.
- // We could have used void for this, but conversion to
- // void* is just to easy.
- //
- struct enable_type;
- }
-
-
- //
- // enable_if for use in adapted iterators constructors.
- //
- // In order to provide interoperability between adapted constant and
- // mutable iterators, adapted iterators will usually provide templated
- // conversion constructors of the following form
- //
- // template <class BaseIterator>
- // class adapted_iterator :
- // public iterator_adaptor< adapted_iterator<Iterator>, Iterator >
- // {
- // public:
- //
- // ...
- //
- // template <class OtherIterator>
- // adapted_iterator(
- // OtherIterator const& it
- // , typename enable_if_convertible<OtherIterator, Iterator>::type* = 0);
- //
- // ...
- // };
- //
- // enable_if_convertible is used to remove those overloads from the overload
- // set that cannot be instantiated. For all practical purposes only overloads
- // for constant/mutable interaction will remain. This has the advantage that
- // meta functions like boost::is_convertible do not return false positives,
- // as they can only look at the signature of the conversion constructor
- // and not at the actual instantiation.
- //
- // enable_if_interoperable can be safely used in user code. It falls back to
- // always enabled for compilers that don't support enable_if or is_convertible.
- // There is no need for compiler specific workarounds in user code.
- //
- // The operators implementation relies on boost::is_convertible not returning
- // false positives for user/library defined iterator types. See comments
- // on operator implementation for consequences.
- //
-# if defined(BOOST_NO_IS_CONVERTIBLE) || defined(BOOST_NO_SFINAE)
-
- template <class From, class To>
- struct enable_if_convertible
- {
- typedef boost::iterators::detail::enable_type type;
- };
-
-# elif BOOST_WORKAROUND(_MSC_FULL_VER, BOOST_TESTED_AT(13102292))
-
- // For some reason vc7.1 needs us to "cut off" instantiation
- // of is_convertible in a few cases.
- template<typename From, typename To>
- struct enable_if_convertible
- : iterators::enable_if<
- mpl::or_<
- is_same<From,To>
- , is_convertible<From, To>
- >
- , boost::iterators::detail::enable_type
- >
- {};
-
-# else
-
- template<typename From, typename To>
- struct enable_if_convertible
- : iterators::enable_if<
- is_convertible<From, To>
- , boost::iterators::detail::enable_type
- >
- {};
-
-# endif
-
- //
- // Default template argument handling for iterator_adaptor
- //
- namespace detail
- {
- // If T is use_default, return the result of invoking
- // DefaultNullaryFn, otherwise return T.
- template <class T, class DefaultNullaryFn>
- struct ia_dflt_help
- : mpl::eval_if<
- is_same<T, use_default>
- , DefaultNullaryFn
- , mpl::identity<T>
- >
- {
- };
-
- // A metafunction which computes an iterator_adaptor's base class,
- // a specialization of iterator_facade.
- template <
- class Derived
- , class Base
- , class Value
- , class Traversal
- , class Reference
- , class Difference
- >
- struct iterator_adaptor_base
- {
- typedef iterator_facade<
- Derived
-
-# ifdef BOOST_ITERATOR_REF_CONSTNESS_KILLS_WRITABILITY
- , typename boost::iterators::detail::ia_dflt_help<
- Value
- , mpl::eval_if<
- is_same<Reference,use_default>
- , iterator_value<Base>
- , remove_reference<Reference>
- >
- >::type
-# else
- , typename boost::iterators::detail::ia_dflt_help<
- Value, iterator_value<Base>
- >::type
-# endif
-
- , typename boost::iterators::detail::ia_dflt_help<
- Traversal
- , iterator_traversal<Base>
- >::type
-
- , typename boost::iterators::detail::ia_dflt_help<
- Reference
- , mpl::eval_if<
- is_same<Value,use_default>
- , iterator_reference<Base>
- , add_reference<Value>
- >
- >::type
-
- , typename boost::iterators::detail::ia_dflt_help<
- Difference, iterator_difference<Base>
- >::type
- >
- type;
- };
-
- // workaround for aC++ CR JAGaf33512
- template <class Tr1, class Tr2>
- inline void iterator_adaptor_assert_traversal ()
- {
- BOOST_STATIC_ASSERT((is_convertible<Tr1, Tr2>::value));
- }
- }
-
- //
- // Iterator Adaptor
- //
- // The parameter ordering changed slightly with respect to former
- // versions of iterator_adaptor The idea is that when the user needs
- // to fiddle with the reference type it is highly likely that the
- // iterator category has to be adjusted as well. Any of the
- // following four template arguments may be ommitted or explicitly
- // replaced by use_default.
- //
- // Value - if supplied, the value_type of the resulting iterator, unless
- // const. If const, a conforming compiler strips constness for the
- // value_type. If not supplied, iterator_traits<Base>::value_type is used
- //
- // Category - the traversal category of the resulting iterator. If not
- // supplied, iterator_traversal<Base>::type is used.
- //
- // Reference - the reference type of the resulting iterator, and in
- // particular, the result type of operator*(). If not supplied but
- // Value is supplied, Value& is used. Otherwise
- // iterator_traits<Base>::reference is used.
- //
- // Difference - the difference_type of the resulting iterator. If not
- // supplied, iterator_traits<Base>::difference_type is used.
- //
- template <
- class Derived
- , class Base
- , class Value = use_default
- , class Traversal = use_default
- , class Reference = use_default
- , class Difference = use_default
- >
- class iterator_adaptor
- : public boost::iterators::detail::iterator_adaptor_base<
- Derived, Base, Value, Traversal, Reference, Difference
- >::type
- {
- friend class iterator_core_access;
-
- protected:
- typedef typename boost::iterators::detail::iterator_adaptor_base<
- Derived, Base, Value, Traversal, Reference, Difference
- >::type super_t;
- public:
- iterator_adaptor() {}
-
- explicit iterator_adaptor(Base const &iter)
- : m_iterator(iter)
- {
- }
-
- typedef Base base_type;
-
- Base const& base() const
- { return m_iterator; }
-
- protected:
- // for convenience in derived classes
- typedef iterator_adaptor<Derived,Base,Value,Traversal,Reference,Difference> iterator_adaptor_;
-
- //
- // lvalue access to the Base object for Derived
- //
- Base const& base_reference() const
- { return m_iterator; }
-
- Base& base_reference()
- { return m_iterator; }
-
- private:
- //
- // Core iterator interface for iterator_facade. This is private
- // to prevent temptation for Derived classes to use it, which
- // will often result in an error. Derived classes should use
- // base_reference(), above, to get direct access to m_iterator.
- //
- typename super_t::reference dereference() const
- { return *m_iterator; }
-
- template <
- class OtherDerived, class OtherIterator, class V, class C, class R, class D
- >
- bool equal(iterator_adaptor<OtherDerived, OtherIterator, V, C, R, D> const& x) const
- {
- // Maybe readd with same_distance
- // BOOST_STATIC_ASSERT(
- // (detail::same_category_and_difference<Derived,OtherDerived>::value)
- // );
- return m_iterator == x.base();
- }
-
- typedef typename iterator_category_to_traversal<
- typename super_t::iterator_category
- >::type my_traversal;
-
-# define BOOST_ITERATOR_ADAPTOR_ASSERT_TRAVERSAL(cat) \
- boost::iterators::detail::iterator_adaptor_assert_traversal<my_traversal, cat>();
-
- void advance(typename super_t::difference_type n)
- {
- BOOST_ITERATOR_ADAPTOR_ASSERT_TRAVERSAL(random_access_traversal_tag)
- m_iterator += n;
- }
-
- void increment() { ++m_iterator; }
-
- void decrement()
- {
- BOOST_ITERATOR_ADAPTOR_ASSERT_TRAVERSAL(bidirectional_traversal_tag)
- --m_iterator;
- }
-
- template <
- class OtherDerived, class OtherIterator, class V, class C, class R, class D
- >
- typename super_t::difference_type distance_to(
- iterator_adaptor<OtherDerived, OtherIterator, V, C, R, D> const& y) const
- {
- BOOST_ITERATOR_ADAPTOR_ASSERT_TRAVERSAL(random_access_traversal_tag)
- // Maybe readd with same_distance
- // BOOST_STATIC_ASSERT(
- // (detail::same_category_and_difference<Derived,OtherDerived>::value)
- // );
- return y.base() - m_iterator;
- }
-
-# undef BOOST_ITERATOR_ADAPTOR_ASSERT_TRAVERSAL
-
- private: // data members
- Base m_iterator;
- };
-
-} // namespace iterators
-
-using iterators::iterator_adaptor;
-using iterators::enable_if_convertible;
-
-} // namespace boost
-
-#include <boost/iterator/detail/config_undef.hpp>
-
-#endif // BOOST_ITERATOR_ADAPTOR_23022003THW_HPP
projects / lyx.git / blobdiff