[NAME]
ALL.dao.data.static

[TITLE]
Static Variables

[DESCRIPTION]

Another type of variable is the static variable which can be declared with the static ke
yword. Static variables must be initialized with constant expressions. 
     
   1  static stat = "static variable"
   2  for( i = 1 : 5 ) {
   3      static stat = 123
   4      for( i > 3 ) {
   5          static stat = "local static variable"
   6          static nested = [1,2,3]
   7          io.writeln( stat )  # Output: local static variable
   8      }
   9      io.writeln( stat )    # Output: 123
  10      io.writeln( nested )  # Error! "nested" not visible here.
  11  }
  12  io.writeln( stat )  # Output: static variable
  13  
  14  static abc = rand(100)  # Error! Expecting constant expression.
     


Outside class body, a static variable is a global variable with strictly local visibility
within its declaration scope. So if a routine with static variables is executed multiple 
times, all the executions will access the same static variables. 
     
   1  routine Test()
   2  {
   3      static aux = 0
   4      aux += 1
   5      io.writeln( aux )
   6  }
   7  Test() # Output: 1
   8  Test() # Output: 2
   9  Test() # Output: 3
     


Similarly, static variables in class are variables shared across different class instance
s, as they are stored in the class objects instead of the instance objects. They can be a
ccessed with the class objects. 
     
   1  class Klass
   2  {
   3      static state = [1,2,3]
   4  }
   5  io.writeln( Klass.state )