ArduinoJson/src/ArduinoJson/Deserialization/DeserializationError.hpp

// ArduinoJson - arduinojson.org
// Copyright Benoit Blanchon 2014-2020
// MIT License

#pragma once

#include <ArduinoJson/Namespace.hpp>

#if ARDUINOJSON_ENABLE_STD_STREAM
#include <ostream>
#endif

namespace ARDUINOJSON_NAMESPACE {

class DeserializationError {
  // safe bool idiom
  typedef void (DeserializationError::*bool_type)() const;
  void safeBoolHelper() const {}

 public:
  enum Code {
    Ok,
    IncompleteInput,
    InvalidInput,
    NoMemory,
    NotSupported,
    TooDeep
  };

  DeserializationError() {}
  DeserializationError(Code c) : _code(c) {}

  // Compare with DeserializationError
  friend bool operator==(const DeserializationError& lhs,
                         const DeserializationError& rhs) {
    return lhs._code == rhs._code;
  }
  friend bool operator!=(const DeserializationError& lhs,
                         const DeserializationError& rhs) {
    return lhs._code != rhs._code;
  }

  // Compare with Code
  friend bool operator==(const DeserializationError& lhs, Code rhs) {
    return lhs._code == rhs;
  }
  friend bool operator==(Code lhs, const DeserializationError& rhs) {
    return lhs == rhs._code;
  }
  friend bool operator!=(const DeserializationError& lhs, Code rhs) {
    return lhs._code != rhs;
  }
  friend bool operator!=(Code lhs, const DeserializationError& rhs) {
    return lhs != rhs._code;
  }

  // Behaves like a bool
  operator bool_type() const {
    return _code != Ok ? &DeserializationError::safeBoolHelper : 0;
  }
  friend bool operator==(bool value, const DeserializationError& err) {
    return static_cast<bool>(err) == value;
  }
  friend bool operator==(const DeserializationError& err, bool value) {
    return static_cast<bool>(err) == value;
  }
  friend bool operator!=(bool value, const DeserializationError& err) {
    return static_cast<bool>(err) != value;
  }
  friend bool operator!=(const DeserializationError& err, bool value) {
    return static_cast<bool>(err) != value;
  }

  // Returns internal enum, useful for switch statement
  Code code() const {
    return _code;
  }

  const char* c_str() const {
    switch (_code) {
      case Ok:
        return "Ok";
      case TooDeep:
        return "TooDeep";
      case NoMemory:
        return "NoMemory";
      case InvalidInput:
        return "InvalidInput";
      case IncompleteInput:
        return "IncompleteInput";
      case NotSupported:
        return "NotSupported";
      default:
        return "???";
    }
  }

 private:
  Code _code;
};

#if ARDUINOJSON_ENABLE_STD_STREAM
inline std::ostream& operator<<(std::ostream& s,
                                const DeserializationError& e) {
  s << e.c_str();
  return s;
}

inline std::ostream& operator<<(std::ostream& s, DeserializationError::Code c) {
  s << DeserializationError(c).c_str();
  return s;
}
#endif

}  // namespace ARDUINOJSON_NAMESPACE