json-validator/include/jvalidate/detail/tribool.h

#pragma once

#include <compare>

#define JVALIDATE_TRIBOOL_TYPE(TypeName, True, False, Maybe)                                       \
  class TypeName {                                                                                 \
  public:                                                                                          \
    enum Enum { True, False, Maybe };                                                              \
                                                                                                   \
  private:                                                                                         \
    Enum state_;                                                                                   \
                                                                                                   \
  public:                                                                                          \
    TypeName(bool state) : state_(state ? True : False) {}                                         \
    TypeName(Enum state) : state_(state) {}                                                        \
                                                                                                   \
    operator Enum() const { return state_; }                                                       \
    explicit operator bool() const { return state_ != False; }                                     \
                                                                                                   \
    friend TypeName operator!(TypeName val) {                                                      \
      if (val.state_ == Maybe) {                                                                   \
        return Maybe;                                                                              \
      }                                                                                            \
      return val.state_ == False ? True : False;                                                   \
    }                                                                                              \
                                                                                                   \
    friend TypeName operator|(TypeName lhs, TypeName rhs) {                                        \
      if (lhs.state_ == Maybe && rhs.state_ == Maybe) {                                            \
        return Maybe;                                                                              \
      }                                                                                            \
      if (lhs.state_ == True || rhs.state_ == True) {                                              \
        return True;                                                                               \
      }                                                                                            \
      return False;                                                                                \
    }                                                                                              \
                                                                                                   \
    friend TypeName operator&(TypeName lhs, TypeName rhs) {                                        \
      if (lhs.state_ == Maybe && rhs.state_ == Maybe) {                                            \
        return Maybe;                                                                              \
      }                                                                                            \
      if (lhs.state_ == False || rhs.state_ == False) {                                            \
        return False;                                                                              \
      }                                                                                            \
      return True;                                                                                 \
    }                                                                                              \
                                                                                                   \
    TypeName & operator&=(TypeName rhs) { return *this = *this & rhs; }                            \
    TypeName & operator|=(TypeName rhs) { return *this = *this | rhs; }                            \
                                                                                                   \
    friend auto operator==(TypeName lhs, TypeName::Enum rhs) {                                     \
      return static_cast<int>(lhs.state_) == static_cast<int>(rhs);                                \
    }                                                                                              \
    friend auto operator!=(TypeName lhs, TypeName::Enum rhs) {                                     \
      return static_cast<int>(lhs.state_) != static_cast<int>(rhs);                                \
    }                                                                                              \
    friend auto operator<=>(TypeName lhs, TypeName rhs) {                                          \
      return static_cast<int>(lhs.state_) <=> static_cast<int>(rhs.state_);                        \
    }                                                                                              \
  }