typedef NS_ENUM(NSUInteger, ETError) {
  UndefinedError = 0x65,
  ModuleNotLoaded = 0x66,
  FileWriteFailed = 0x67,
  InvalidModelSource = 0xff,

  Ok = 0x00,
  Internal = 0x01,
  InvalidState = 0x02,
  EndOfMethod = 0x03,

  NotSupported = 0x10,
  NotImplemented = 0x11,
  InvalidArgument = 0x12,
  InvalidType = 0x13,
  OperatorMissing = 0x14,

  NotFound = 0x20,
  MemoryAllocationFailed = 0x21,
  AccessFailed = 0x22,
  InvalidProgram = 0x23,

  DelegateInvalidCompatibility = 0x30,
  DelegateMemoryAllocationFailed = 0x31,
  DelegateInvalidHandle = 0x32
};