98 lines
2.3 KiB
C++
98 lines
2.3 KiB
C++
//
|
|
// immer: immutable data structures for C++
|
|
// Copyright (C) 2016, 2017, 2018 Juan Pedro Bolivar Puente
|
|
//
|
|
// This software is distributed under the Boost Software License, Version 1.0.
|
|
// See accompanying file LICENSE or copy at http://boost.org/LICENSE_1_0.txt
|
|
//
|
|
|
|
#pragma once
|
|
|
|
#include <immer/detail/iterator_facade.hpp>
|
|
#include <immer/detail/rbts/rrbtree.hpp>
|
|
|
|
namespace immer {
|
|
namespace detail {
|
|
namespace rbts {
|
|
|
|
template <typename T, typename MP, bits_t B, bits_t BL>
|
|
struct rrbtree_iterator
|
|
: iterator_facade<rrbtree_iterator<T, MP, B, BL>,
|
|
std::random_access_iterator_tag,
|
|
T,
|
|
const T&,
|
|
std::ptrdiff_t,
|
|
const T*>
|
|
{
|
|
using tree_t = rrbtree<T, MP, B, BL>;
|
|
using region_t = std::tuple<const T*, size_t, size_t>;
|
|
|
|
struct end_t
|
|
{};
|
|
|
|
const tree_t& impl() const { return *v_; }
|
|
size_t index() const { return i_; }
|
|
|
|
rrbtree_iterator() = default;
|
|
|
|
rrbtree_iterator(const tree_t& v)
|
|
: v_{&v}
|
|
, i_{0}
|
|
, curr_{nullptr, ~size_t{}, ~size_t{}}
|
|
{}
|
|
|
|
rrbtree_iterator(const tree_t& v, end_t)
|
|
: v_{&v}
|
|
, i_{v.size}
|
|
, curr_{nullptr, ~size_t{}, ~size_t{}}
|
|
{}
|
|
|
|
private:
|
|
friend iterator_core_access;
|
|
|
|
const tree_t* v_;
|
|
size_t i_;
|
|
mutable region_t curr_;
|
|
|
|
void increment()
|
|
{
|
|
using std::get;
|
|
assert(i_ < v_->size);
|
|
++i_;
|
|
}
|
|
|
|
void decrement()
|
|
{
|
|
using std::get;
|
|
assert(i_ > 0);
|
|
--i_;
|
|
}
|
|
|
|
void advance(std::ptrdiff_t n)
|
|
{
|
|
using std::get;
|
|
assert(n <= 0 || i_ + static_cast<size_t>(n) <= v_->size);
|
|
assert(n >= 0 || static_cast<size_t>(-n) <= i_);
|
|
i_ += n;
|
|
}
|
|
|
|
bool equal(const rrbtree_iterator& other) const { return i_ == other.i_; }
|
|
|
|
std::ptrdiff_t distance_to(const rrbtree_iterator& other) const
|
|
{
|
|
return other.i_ > i_ ? static_cast<std::ptrdiff_t>(other.i_ - i_)
|
|
: -static_cast<std::ptrdiff_t>(i_ - other.i_);
|
|
}
|
|
|
|
const T& dereference() const
|
|
{
|
|
using std::get;
|
|
if (i_ < get<1>(curr_) || i_ >= get<2>(curr_))
|
|
curr_ = v_->region_for(i_);
|
|
return get<0>(curr_)[i_ - get<1>(curr_)];
|
|
}
|
|
};
|
|
|
|
} // namespace rbts
|
|
} // namespace detail
|
|
} // namespace immer
|