hash.hpp

/*
 * glslstruct - a C++ library designed to easily represent GLSL's Uniform Buffer Objects (UBOs) and Shader Storage Buffer Objects (SSBOs) in C++.
 *
 * Licensed under the BSD 3-Clause License with Attribution Requirement.
 * See the LICENSE file for details: https://github.com/MAIPA01/glslstruct/blob/main/LICENSE
 *
 * Copyright (c) 2025, Patryk Antosik (MAIPA01)
 */
 
#pragma once
#ifndef _GLSL_STRUCT_HASH_HPP_
    #define _GLSL_STRUCT_HASH_HPP_
 
    #include <glslstruct/config.hpp>
 
    #if !_GLSL_STRUCT_HAS_CXX17
_GLSL_STRUCT_ERROR("This is only available for c++17 and greater!");
    #else
 
        #include <glslstruct/libs.hpp>
 
namespace glslstruct::utils {
        #if _GLSL_STRUCT_HAS_CXX20
    /**
     * @brief Checks if type has defined std::hash
     * @ingroup utils
     * @tparam T type
     */
    template<class T> concept hashable = requires { typename std::hash<T>; };
 
    /**
     * @brief Checks if type has defined std::hash
     * @ingroup utils
     * @tparam T type
     */
    template<class T>
    static _GLSL_STRUCT_CONSTEXPR17 bool is_hashable_v = hashable<T>;
 
    /**
     * @brief Checks if type has defined std::hash
     * @ingroup utils
     * @tparam T type
     */
    template<class T>
    struct is_hashable : std::bool_constant<is_hashable_v<T> > {};
        #else
    /**
     * @brief Checks if type has defined std::hash
     * @ingroup utils
     * @tparam T type
     */
    template<class T, class = void>
    struct is_hashable : std::false_type {};
 
    /**
     * @brief Checks if type has defined std::hash
     * @ingroup utils
     * @tparam T type
     */
    template<class T>
    struct is_hashable<T, std::void_t<std::hash<T> > > : std::true_type {};
 
    /**
     * @brief Checks if type has defined std::hash
     * @ingroup utils
     * @tparam T type
     */
    template<class T>
    static _GLSL_STRUCT_CONSTEXPR17 bool is_hashable_v = is_hashable<T>::value;
        #endif
} // namespace glslstruct::utils
 
    #endif
#endif