//
// 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/rbts/rbtree.hpp>
#include <immer/detail/rbts/rbtree_iterator.hpp>
#include <immer/memory_policy.hpp>
namespace immer {
template <typename T,
typename MemoryPolicy,
detail::rbts::bits_t B,
detail::rbts::bits_t BL>
class vector;
template <typename T,
typename MemoryPolicy,
detail::rbts::bits_t B,
detail::rbts::bits_t BL>
class flex_vector_transient;
/*!
* Mutable version of `immer::vector`.
*
* @rst
*
* Refer to :doc:`transients` to learn more about when and how to use
* the mutable versions of immutable containers.
*
* @endrst
*/
template <typename T,
typename MemoryPolicy = default_memory_policy,
detail::rbts::bits_t B = default_bits,
detail::rbts::bits_t BL =
detail::rbts::derive_bits_leaf<T, MemoryPolicy, B>>
class vector_transient : MemoryPolicy::transience_t::owner
{
using impl_t = detail::rbts::rbtree<T, MemoryPolicy, B, BL>;
using flex_t = flex_vector_transient<T, MemoryPolicy, B, BL>;
using owner_t = typename MemoryPolicy::transience_t::owner;
public:
static constexpr auto bits = B;
static constexpr auto bits_leaf = BL;
using memory_policy = MemoryPolicy;
using value_type = T;
using reference = const T&;
using size_type = detail::rbts::size_t;
using difference_type = std::ptrdiff_t;
using const_reference = const T&;
using iterator = detail::rbts::rbtree_iterator<T, MemoryPolicy, B, BL>;
using const_iterator = iterator;
using reverse_iterator = std::reverse_iterator<iterator>;
using persistent_type = vector<T, MemoryPolicy, B, BL>;
/*!
* Default constructor. It creates a mutable vector of `size() ==
* 0`. It does not allocate memory and its complexity is
* @f$ O(1) @f$.
*/
vector_transient() = default;
/*!
* Returns an iterator pointing at the first element of the
* collection. It does not allocate memory and its complexity is
* @f$ O(1) @f$.
*/
IMMER_NODISCARD iterator begin() const { return {impl_}; }
/*!
* Returns an iterator pointing just after the last element of the
* collection. It does not allocate and its complexity is @f$ O(1) @f$.
*/
IMMER_NODISCARD iterator end() const
{
return {impl_, typename iterator::end_t{}};
}
/*!
* Returns an iterator that traverses the collection backwards,
* pointing at the first element of the reversed collection. It
* does not allocate memory and its complexity is @f$ O(1) @f$.
*/
IMMER_NODISCARD reverse_iterator rbegin() const
{
return reverse_iterator{end()};
}
/*!
* Returns an iterator that traverses the collection backwards,
* pointing after the last element of the reversed collection. It
* does not allocate memory and its complexity is @f$ O(1) @f$.
*/
IMMER_NODISCARD reverse_iterator rend() const
{
return reverse_iterator{begin()};
}
/*!
* Returns the number of elements in the container. It does
* not allocate memory and its complexity is @f$ O(1) @f$.
*/
IMMER_NODISCARD size_type size() const { return impl_.size; }
/*!
* Returns `true` if there are no elements in the container. It
* does not allocate memory and its complexity is @f$ O(1) @f$.
*/
IMMER_NODISCARD bool empty() const { return impl_.size == 0; }
/*!
* Returns a `const` reference to the element at position `index`.
* It is undefined when @f$ 0 index \geq size() @f$. It does not
* allocate memory and its complexity is *effectively* @f$ O(1)
* @f$.
*/
reference operator[](size_type index) const { return impl_.get(index); }
/*!
* Returns a `const` reference to the element at position
* `index`. It throws an `std::out_of_range` exception when @f$
* index \geq size() @f$. It does not allocate memory and its
* complexity is *effectively* @f$ O(1) @f$.
*/
reference at(size_type index) const { return impl_.get_check(index); }
/*!
* Inserts `value` at the end. It may allocate memory and its
* complexity is *effectively* @f$ O(1) @f$.
*/
void push_back(value_type value)
{
impl_.push_back_mut(*this, std::move(value));
}
/*!
* Sets to the value `value` at position `idx`.
* Undefined for `index >= size()`.
* It may allocate memory and its complexity is
* *effectively* @f$ O(1) @f$.
*/
void set(size_type index, value_type value)
{
impl_.assoc_mut(*this, index, std::move(value));
}
/*!
* Updates the vector to contain the result of the expression
* `fn((*this)[idx])` at position `idx`.
* Undefined for `0 >= size()`.
* It may allocate memory and its complexity is
* *effectively* @f$ O(1) @f$.
*/
template <typename FnT>
void update(size_type index, FnT&& fn)
{
impl_.update_mut(*this, index, std::forward<FnT>(fn));
}
/*!
* Resizes the vector to only contain the first `min(elems, size())`
* elements. It may allocate memory and its complexity is
* *effectively* @f$ O(1) @f$.
*/
void take(size_type elems) { impl_.take_mut(*this, elems); }
/*!
* Returns an @a immutable form of this container, an
* `immer::vector`.
*/
IMMER_NODISCARD persistent_type persistent() &
{
this->owner_t::operator=(owner_t{});
return persistent_type{impl_};
}
IMMER_NODISCARD persistent_type persistent() &&
{
return persistent_type{std::move(impl_)};
}
private:
friend flex_t;
friend persistent_type;
vector_transient(impl_t impl)
: impl_(std::move(impl))
{}
impl_t impl_ = impl_t::empty();
};
} // namespace immer
