Source/WTF/wtf/EnumClassOperatorOverloads.h

/*
 * Copyright (C) 2019 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
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 *
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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#pragma once

#include <type_traits>

#define OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, op, enableExpression) \
    template<typename T> \
    constexpr auto operator op(enumName enumEntry, T value) -> std::enable_if_t<(enableExpression), T> \
    { \
        return static_cast<T>(enumEntry) op value; \
    } \
    \
    template<typename T> \
    constexpr auto operator op(T value, enumName enumEntry) -> std::enable_if_t<(enableExpression), T> \
    { \
        return value op static_cast<T>(enumEntry); \
    } \

#define OVERLOAD_MATH_OPERATORS_FOR_ENUM_CLASS_WHEN(enumName, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, +, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, -, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, *, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, /, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, %, enableExpression) \

#define OVERLOAD_MATH_OPERATORS_FOR_ENUM_CLASS_WITH_INTEGRALS(enumName) OVERLOAD_MATH_OPERATORS_FOR_ENUM_CLASS_WHEN(enumName, std::is_integral_v<T>)

#define OVERLOAD_RELATIONAL_OPERATORS_FOR_ENUM_CLASS_WHEN(enumName, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, ==, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, !=, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, <, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, <=, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, >, enableExpression) \
    OVERLOAD_OPERATOR_FOR_ENUM_CLASS_WHEN(enumName, >=, enableExpression) \

#define OVERLOAD_RELATIONAL_OPERATORS_FOR_ENUM_CLASS_WITH_INTEGRALS(enumName) OVERLOAD_RELATIONAL_OPERATORS_FOR_ENUM_CLASS_WHEN(enumName, std::is_integral_v<T>)