Enumeration in swift
  Enumerations   An  enumeration  defines a common type for a group of related values and enables you to work with those values in a type-safe way within your code.   enum  Direction {      case  north      case  south      case  east      case  west  }      Note  :     Unlike C and Objective C, Here enum is not initialized with a default value.   The name must start with a Capital letter.     var  direction  = Direction. west   or  var  direction  = . west     If the  case  for  .west  is omitted, this code does not compile, because it does not consider the complete list of  CompassPoint  cases.     When it is not appropriate to provide a  case  for every enumeration case, you can provide a  default  case to cover any cases that are not addressed explicitly:        switch  somePlanet  {  case  . earth :      print ( "Mostly harmless" )  default :      print ( "Not a safe place for humans" )  } Associated Values      ...