types.hpp

/*
 * live_cells_cpp
 * Copyright (C) 2024  Alexander Gutev <alex.gutev@gmail.com>
 *
 * 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.
 */
 
#ifndef LIVE_CELLS_TYPES_HPP
#define LIVE_CELLS_TYPES_HPP
 
#include <concepts>
#include <utility>
 
#include "keys.hpp"
 
namespace live_cells {
 
    class observer {
    public:
        typedef std::shared_ptr<observer> ref;
 
        virtual ~observer() noexcept = default;
 
        virtual void will_update(const key_ref &k) = 0;
 
        virtual void update(const key_ref &k, bool did_change) = 0;
    };
 
    template <typename T>
    concept Keyable = requires(const T &o) {
        { o.key() } -> std::same_as<key_ref>;
    };
 
    template <typename T>
    concept Trackable = requires(const T &o) {
        { o() } -> std::same_as<decltype(o.value())>;
    };
 
    template <typename T>
    concept Cell = requires(const T &o) {
        { o.add_observer(observer::ref()) };
        { o.remove_observer(observer::ref()) };
        { o.value() } -> std::same_as<typename T::value_type>;
        { o() } -> std::same_as<typename T::value_type>;
        { o.key() } -> std::same_as<key_ref>;
    };
 
    template <typename C, typename T>
    concept TypedCell = Cell<C> && std::convertible_to<typename C::value_type, T>;
 
    template <typename C>
    concept MutableCell = Cell<C> && requires(C c) {
        { c.value(std::declval<typename C::value_type>()) };
    };
 
    template <typename C, typename T>
    concept TypedMutableCell = TypedCell<C,T> && MutableCell<C>;
 
    namespace ops {
 
        template <typename Op, typename C>
        concept Operator = requires(const Op &op) {
            { op(std::declval<C>()) } -> Cell;
        };
 
        template <Cell C, Operator<C> O>
        inline auto operator|(const C &arg, const O &op) {
            return op(arg);
        }
 
    }  // ops
 
}  // live_cells
 
#endif /* LIVE_CELLS_TYPES_HPP */