lyx_mirror/boost/boost/half_open_range.hpp
Lars Gullik Bjønnes 59b6a4701a major boost update
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@4179 a592a061-630c-0410-9148-cb99ea01b6c8
2002-05-21 23:39:58 +00:00

427 lines
12 KiB
C++

// (C) Copyright Jeremy Siek and David Abrahams 2000-2001. Permission to copy,
// use, modify, sell and distribute this software is granted provided this
// copyright notice appears in all copies. This software is provided "as is"
// without express or implied warranty, and with no claim as to its suitability
// for any purpose.
//
// Revision History:
// 11 Feb 2001 Use new iterator_adaptor interface, Fixes for Borland.
// (Dave Abrahams)
// 04 Feb 2001 Support for user-defined iterator categories (Dave Abrahams)
// 30 Jan 2001 Initial Checkin (Dave Abrahams)
#ifndef BOOST_HALF_OPEN_RANGE_HPP_
# define BOOST_HALF_OPEN_RANGE_HPP_
# include <boost/counting_iterator.hpp>
# include <functional>
# include <cassert>
# include <boost/operators.hpp>
# include <string>
# include <stdexcept>
# include <iterator>
namespace boost {
namespace detail {
// Template class choose_finish -- allows us to maintain the invariant that
// start() <= finish() on half_open_range specializations that support random
// access.
#ifdef __MWERKS__
template <class T>
const T& choose_finish(const T&, const T& finish, std::input_iterator_tag)
{
return finish;
}
template <class T>
const T& choose_finish(const T&, const T& finish, std::output_iterator_tag)
{
return finish;
}
template <class T>
const T& choose_finish(const T& start, const T& finish, std::random_access_iterator_tag)
{
return finish < start ? start : finish;
}
#else
template <bool is_random_access> struct finish_chooser;
template <>
struct finish_chooser<false>
{
template <class T>
struct rebind
{
static T choose(const T&, const T& finish)
{ return finish; }
};
};
template <>
struct finish_chooser<true>
{
template <class T>
struct rebind
{
static T choose(const T& start, const T& finish)
{ return finish < start ? start : finish; }
};
};
template <class Category, class Incrementable>
struct choose_finish
{
static const Incrementable choose(const Incrementable& start, const Incrementable& finish)
{
return finish_chooser<(
::boost::is_convertible<Category*,std::random_access_iterator_tag*>::value
)>::template rebind<Incrementable>::choose(start, finish);
}
};
#endif
}
template <class Incrementable>
struct half_open_range
{
typedef typename counting_iterator_generator<Incrementable>::type iterator;
private: // utility type definitions
// Using iter_t prevents compiler confusion with boost::iterator
typedef typename counting_iterator_generator<Incrementable>::type iter_t;
typedef std::less<Incrementable> less_value;
typedef typename iter_t::iterator_category category;
typedef half_open_range<Incrementable> self;
public:
typedef iter_t const_iterator;
typedef typename iterator::value_type value_type;
typedef typename iterator::difference_type difference_type;
typedef typename iterator::reference reference;
typedef typename iterator::reference const_reference;
typedef typename iterator::pointer pointer;
typedef typename iterator::pointer const_pointer;
// It would be nice to select an unsigned type, but this is appropriate
// since the library makes an attempt to select a difference_type which can
// hold the difference between any two iterators.
typedef typename iterator::difference_type size_type;
half_open_range(Incrementable start, Incrementable finish)
: m_start(start),
m_finish(
#ifndef __MWERKS__
detail::choose_finish<category,Incrementable>::choose(start, finish)
#else
detail::choose_finish(start, finish, category())
#endif
)
{}
// Implicit conversion from std::pair<Incrementable,Incrementable> allows us
// to accept the results of std::equal_range(), for example.
half_open_range(const std::pair<Incrementable,Incrementable>& x)
: m_start(x.first),
m_finish(
#ifndef __MWERKS__
detail::choose_finish<category,Incrementable>::choose(x.first, x.second)
#else
detail::choose_finish(x.first, x.second, category())
#endif
)
{}
half_open_range& operator=(const self& x)
{
m_start = x.m_start;
m_finish = x.m_finish;
return *this;
}
half_open_range& operator=(const std::pair<Incrementable,Incrementable>& x)
{
m_start = x.first;
m_finish =
#ifndef __MWERKS__
detail::choose_finish<category,Incrementable>::choose(x.first, x.second);
#else
detail::choose_finish(x.first, x.second, category();
#endif
}
iterator begin() const { return iterator(m_start); }
iterator end() const { return iterator(m_finish); }
Incrementable front() const { assert(!this->empty()); return m_start; }
Incrementable back() const { assert(!this->empty()); return boost::prior(m_finish); }
Incrementable start() const { return m_start; }
Incrementable finish() const { return m_finish; }
size_type size() const { return boost::detail::distance(begin(), end()); }
bool empty() const
{
return m_finish == m_start;
}
void swap(half_open_range& x) {
std::swap(m_start, x.m_start);
std::swap(m_finish, x.m_finish);
}
public: // functions requiring random access elements
// REQUIRES: x is reachable from this->front()
bool contains(const value_type& x) const
{
BOOST_STATIC_ASSERT((boost::is_same<category, std::random_access_iterator_tag>::value));
return !less_value()(x, m_start) && less_value()(x, m_finish);
}
bool contains(const half_open_range& x) const
{
BOOST_STATIC_ASSERT((boost::is_same<category, std::random_access_iterator_tag>::value));
return x.empty() || !less_value()(x.m_start, m_start) && !less_value()(m_finish, x.m_finish);
}
bool intersects(const half_open_range& x) const
{
BOOST_STATIC_ASSERT((boost::is_same<category, std::random_access_iterator_tag>::value));
return less_value()(
less_value()(this->m_start, x.m_start) ? x.m_start : this->m_start,
less_value()(this->m_finish, x.m_finish) ? this->m_finish : x.m_finish);
}
half_open_range& operator&=(const half_open_range& x)
{
BOOST_STATIC_ASSERT((boost::is_same<category, std::random_access_iterator_tag>::value));
if (less_value()(this->m_start, x.m_start))
this->m_start = x.m_start;
if (less_value()(x.m_finish, this->m_finish))
this->m_finish = x.m_finish;
if (less_value()(this->m_finish, this->m_start))
this->m_start = this->m_finish;
return *this;
}
half_open_range& operator|=(const half_open_range& x)
{
BOOST_STATIC_ASSERT((boost::is_same<category, std::random_access_iterator_tag>::value));
if (!x.empty())
{
if (this->empty())
{
*this = x;
}
else
{
if (less_value()(x.m_start, this->m_start))
this->m_start = x.m_start;
if (less_value()(this->m_finish, x.m_finish))
this->m_finish = x.m_finish;
}
}
return *this;
}
// REQUIRES: x is reachable from this->front()
const_iterator find(const value_type& x) const
{
BOOST_STATIC_ASSERT((boost::is_same<category, std::random_access_iterator_tag>::value));
return const_iterator(this->contains(x) ? x : m_finish);
}
// REQUIRES: index >= 0 && index < size()
value_type operator[](size_type index) const
{
assert(index >= 0 && index < size());
return m_start + index;
}
value_type at(size_type index) const
{
if (index < 0 || index >= size())
throw std::out_of_range(std::string("half_open_range"));
return m_start + index;
}
private: // data members
Incrementable m_start, m_finish;
};
template <class Incrementable>
half_open_range<Incrementable> operator|(
half_open_range<Incrementable> x,
const half_open_range<Incrementable>& y)
{
return x |= y;
}
template <class Incrementable>
half_open_range<Incrementable> operator&(
half_open_range<Incrementable> x,
const half_open_range<Incrementable>& y)
{
return x &= y;
}
template <class Incrementable>
inline bool operator==(
const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
const bool y_empty = y.empty();
return x.empty() ? y_empty : !y_empty && x.start() == y.start() && x.finish() == y.finish();
}
template <class Incrementable>
inline bool operator!=(
const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
return !(x == y);
}
template <class Incrementable>
inline half_open_range<Incrementable>
make_half_open_range(Incrementable first, Incrementable last)
{
return half_open_range<Incrementable>(first, last);
}
template <class Incrementable>
bool intersects(
const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
return x.intersects(y);
}
template <class Incrementable>
bool contains(
const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
return x.contains(y);
}
} // namespace boost
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
namespace std {
template <class Incrementable> struct less<boost::half_open_range<Incrementable> >
: binary_function<
boost::half_open_range<Incrementable>,
boost::half_open_range<Incrementable>,bool>
{
bool operator()(
const boost::half_open_range<Incrementable>& x,
const boost::half_open_range<Incrementable>& y) const
{
less<Incrementable> cmp;
return !y.empty() && (
cmp(x.start(), y.start())
|| !cmp(y.start(), x.start())
&& cmp(x.finish(), y.finish()));
}
};
template <class Incrementable> struct less_equal<boost::half_open_range<Incrementable> >
: binary_function<
boost::half_open_range<Incrementable>,
boost::half_open_range<Incrementable>,bool>
{
bool operator()(
const boost::half_open_range<Incrementable>& x,
const boost::half_open_range<Incrementable>& y) const
{
typedef boost::half_open_range<Incrementable> range;
less<range> cmp;
return !cmp(y,x);
}
};
template <class Incrementable> struct greater<boost::half_open_range<Incrementable> >
: binary_function<
boost::half_open_range<Incrementable>,
boost::half_open_range<Incrementable>,bool>
{
bool operator()(
const boost::half_open_range<Incrementable>& x,
const boost::half_open_range<Incrementable>& y) const
{
typedef boost::half_open_range<Incrementable> range;
less<range> cmp;
return cmp(y,x);
}
};
template <class Incrementable> struct greater_equal<boost::half_open_range<Incrementable> >
: binary_function<
boost::half_open_range<Incrementable>,
boost::half_open_range<Incrementable>,bool>
{
bool operator()(
const boost::half_open_range<Incrementable>& x,
const boost::half_open_range<Incrementable>& y) const
{
typedef boost::half_open_range<Incrementable> range;
less<range> cmp;
return !cmp(x,y);
}
};
} // namespace std
#else
namespace boost {
// Can't partially specialize std::less et al, so we must provide the operators
template <class Incrementable>
bool operator<(const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
return !y.empty() && (
x.empty() || std::less<Incrementable>()(x.start(), y.start())
|| !std::less<Incrementable>()(y.start(), x.start())
&& std::less<Incrementable>()(x.finish(), y.finish()));
}
template <class Incrementable>
bool operator>(const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
return y < x;
}
template <class Incrementable>
bool operator<=(const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
return !(y < x);
}
template <class Incrementable>
bool operator>=(const half_open_range<Incrementable>& x,
const half_open_range<Incrementable>& y)
{
return !(x < y);
}
} // namespace boost
#endif
#endif // BOOST_HALF_OPEN_RANGE_HPP_