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Declare test_it(variable)

Global variable=#False


Debug "value of variable:"+Str(variable)
test_it(#False)
Debug "value of variable:"+Str(variable)


End


Procedure test_it(variable)
  variable=#True
  ProcedureReturn #False
EndProcedure

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EnableExplicit
Procedure test_ByVal(variable)
  ; variable is passed by value.
  ; Even though it matches name of a Global variable
  ; it does not change the Global value.
  variable=1
  ProcedureReturn 0
EndProcedure
Procedure test_ByRef(*variable.Integer)
  ; variable is passed by reference.
  ; This changes the Global value.
  *variable\i=1
  ProcedureReturn 0
EndProcedure
Global variable=0
Debug "BEFORE TEST variable = "+Str(variable)
test_ByVal(variable)
Debug "AFTER ByVal variable = "+Str(variable)
test_ByRef(@variable)
Debug "AFTER ByRef variable = "+Str(variable)

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;// Precedence for scope of variables (and not prototypes, structures, enumerations, procedures, etc.)  //

;The first declared prohibits further declaration of all others having the same name that are active in the current scope.

;--- Outside procedure ---

     Global      (global scope)
     Threaded    (global scope)
     Define      (local scope to main code outside procedures)


;--- Inside procedure ---

     parameter  (local scope to procedure)
     Global     (global scope)
     Threaded   (global scope)
     
     Protected  (local scope, can be defined after a Global and will override Global's scope)
     Static     (local scope)
     Define     (local scope, can also repeat the declaration of a parameter, i.e. they are equivalent except Define can also assign an initial value)