Transferring procedure and function parameters

By default, method, procedure and function parameters are transferred using references, i.e. when you change formal parameter within a procedure or a function, actual parameter also changes. When a parameter is transferred through value, changes of formal parameter do not influence actual parameter of procedure call. Use Valkeyword to specify that a parameter has to be transferred by value.

If you specify a default value and if this parameter is the last in the list, you can omit it from the list of transferred actual parameters and do not put a comma before this parameter.

If a parameter doesn't have a default value, you can omit it in the list of actual parameters, but you should place a comma separator.

If you omit a parameter, it is either assigned a default value (if available) or Undefinedvalue.

If you do not transfer any parameters during method, procedure or function call (empty parameter list), you still have to use round brackets.

Example:

Var Glob; // Function description Function MyFunction(Val Par1, Par2, Par3) Export     Loc = Glob + Par1 + Par2 + Par3;     Par1 = 40;     Return Loc; EndFunction; // Procedure description Procedure MyProcedure(Par1, Par2, Par3) Export     Loc = Glob + Par1 + Par2 + Par3;     Par1 = 40; EndProcedure; Glob = 100; A = 10; Res = MyFunction(A, 10, 10); // Function call // Here Res = 130, and the variable A = 10, although in function body // the Par1 value is changed to 40. MyProcedure(A, 10, 10); // Procedure call // Here the variable A = 40, because in the procedure body // the Par1 value is changed to 40.