Danny Robson
6065aa9933
compares each index of the two parameters in sequence, returning true if the first parameter has the first value that compares less than the second.
60 lines
2.0 KiB
C++
60 lines
2.0 KiB
C++
/*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
* Copyright 2012-2017 Danny Robson <danny@nerdcruft.net>
|
|
*/
|
|
|
|
#ifndef __UTIL_TYPES_COMPARATOR_HPP
|
|
#define __UTIL_TYPES_COMPARATOR_HPP
|
|
|
|
#include <memory>
|
|
|
|
#include "./iterator.hpp"
|
|
|
|
namespace util::comparator {
|
|
template <typename T>
|
|
struct pointer_comparator {
|
|
bool operator() (const std::unique_ptr<T> &lhs, const std::unique_ptr<T> &rhs);
|
|
bool operator() (const T *lhs, const std::unique_ptr<T> &rhs);
|
|
bool operator() (const std::unique_ptr<T> &lhs, const T *rhs);
|
|
};
|
|
|
|
|
|
///////////////////////////////////////////////////////////////////////////
|
|
/// Provides a comparison interface for types exposing an index operator.
|
|
///
|
|
/// Will return true if the first parameter has the first index that
|
|
/// compares less than the second parameter. Useful for providing a total
|
|
/// order of coordinate types where this doesn't make sense by default.
|
|
///
|
|
/// \tparam T The container data type to compare. Must provide an index
|
|
/// operator.
|
|
template <typename T>
|
|
struct indexed {
|
|
constexpr
|
|
bool operator() (const T &a, const T &b)
|
|
{
|
|
for (auto x: util::zip (a, b)) {
|
|
const auto &[i,j] = x; // clang-4.0: workaround for segfault.
|
|
if (i < j) return true;
|
|
if (i != j) return false;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
};
|
|
}
|
|
|
|
#include "./comparator.ipp"
|
|
#endif
|