pointer.hpp

// This file is part of the ACTS project.
//
// Copyright (C) 2016 CERN for the benefit of the ACTS project
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at https://mozilla.org/MPL/2.0/.
 
#pragma once
 
// Project include(s)
#include "detray/definitions/detail/qualifiers.hpp"
#include "detray/utils/ranges/ranges.hpp"
 
namespace detray::ranges {

template <typename value_t>
class pointer_view
    : public detray::ranges::view_interface<pointer_view<value_t>> {
 public:
  using iterator_t = value_t*;

  pointer_view() = default;

  DETRAY_HOST_DEVICE constexpr explicit pointer_view(value_t& value)
      : m_value{&value} {}

  DETRAY_HOST_DEVICE
  constexpr auto operator*() const -> const value_t& { return *m_value; }

  DETRAY_HOST_DEVICE
  constexpr auto operator*() -> value_t& { return *m_value; }

  DETRAY_HOST_DEVICE
  constexpr auto begin() noexcept -> value_t* { return m_value; }

  DETRAY_HOST_DEVICE
  constexpr auto begin() const noexcept -> const value_t* { return m_value; }

  DETRAY_HOST_DEVICE
  constexpr auto end() noexcept -> value_t* { return m_value + 1; }

  DETRAY_HOST_DEVICE
  constexpr auto end() const noexcept -> const value_t* { return m_value + 1; }

  DETRAY_HOST_DEVICE
  constexpr auto data() noexcept -> value_t* { return m_value; }

  DETRAY_HOST_DEVICE
  constexpr auto data() const noexcept -> const value_t* { return m_value; }

  DETRAY_HOST_DEVICE
  static constexpr auto size() noexcept -> std::size_t { return 1; }

  DETRAY_HOST_DEVICE
  constexpr auto front() noexcept -> value_t { return *m_value; }

  DETRAY_HOST_DEVICE
  constexpr auto back() noexcept -> value_t { return *m_value; }

  DETRAY_HOST_DEVICE constexpr auto operator[](const dindex /*unused*/) const
      -> value_t {
    return *m_value;
  }
 
 private:
  value_t* m_value{};
};
 
namespace views {

template <typename value_t>
struct pointer : public detray::ranges::pointer_view<const value_t> {
  using base_type = detray::ranges::pointer_view<const value_t>;
 
  constexpr pointer() = default;

  template <typename deduced_value_t>
  DETRAY_HOST_DEVICE constexpr explicit pointer(deduced_value_t& value)
      : base_type(value) {}
};
 
// deduction guides
 
template <typename deduced_value_t>
DETRAY_HOST_DEVICE_DEDUCTION_GUIDE pointer(deduced_value_t&)
    -> pointer<deduced_value_t>;
 
}  // namespace views
 
}  // namespace detray::ranges