ladybird/AK/SinglyLinkedListWithCount.h
Lenny Maiorani 5cee5725e7 SinglyLinkedListWithCount: Correctly pass args to append, insert_before, insert_after
Problem:
- Using regular functions rather than function templates results in
  the arguments not being deduced. This then requires the same
  function to be written multiple times and for `move` to be used
  rather than `forward`.

Solution:
- Collapse multiple function overloads to a single function template
  with a deduced argument. This allows the argument to be a forwarding
  reference and bind to either an l-value or r-value and forward the
  value.
2021-01-31 10:48:12 +01:00

154 lines
3.8 KiB
C++

/*
* Copyright (c) 2020, Brian Gianforcaro <b.gianfo@gmail.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/SinglyLinkedList.h>
#include <AK/StdLibExtras.h>
namespace AK {
template<typename T>
class SinglyLinkedListWithCount : private SinglyLinkedList<T> {
public:
SinglyLinkedListWithCount() = default;
~SinglyLinkedListWithCount() = default;
using List = SinglyLinkedList<T>;
using List::is_empty;
using List::size_slow;
inline size_t size() const
{
return m_count;
}
void clear()
{
List::clear();
m_count = 0;
}
T& first()
{
return List::first();
}
const T& first() const
{
return List::first();
}
T& last()
{
return List::last();
}
const T& last() const
{
return List::last();
}
T take_first()
{
m_count--;
return List::take_first();
}
template<typename U = T>
void append(U&& value)
{
m_count++;
return List::append(forward<T>(value));
}
bool contains_slow(const T& value) const
{
return List::contains_slow(value);
}
using Iterator = typename List::Iterator;
friend Iterator;
Iterator begin() { return List::begin(); }
Iterator end() { return List::end(); }
using ConstIterator = typename List::ConstIterator;
friend ConstIterator;
ConstIterator begin() const { return List::begin(); }
ConstIterator end() const { return List::end(); }
template<typename TUnaryPredicate>
ConstIterator find(TUnaryPredicate&& pred) const
{
return List::find_if(forward<TUnaryPredicate>(pred));
}
template<typename TUnaryPredicate>
Iterator find(TUnaryPredicate&& pred)
{
return List::find_if(forward<TUnaryPredicate>(pred));
}
ConstIterator find(const T& value) const
{
return List::find(value);
}
Iterator find(const T& value)
{
return List::find(value);
}
void remove(Iterator iterator)
{
m_count--;
return List::remove(iterator);
}
template<typename U = T>
void insert_before(Iterator iterator, U&& value)
{
m_count++;
List::insert_before(iterator, forward<T>(value));
}
template<typename U = T>
void insert_after(Iterator iterator, U&& value)
{
m_count++;
List::insert_after(iterator, forward<T>(value));
}
private:
size_t m_count { 0 };
};
}
using AK::SinglyLinkedListWithCount;