Call of method in ST

Syntax 
( * internal call of method of the current function block *)
THIS.method-name();|method-name();
THIS.method-name|method-name
  (input_1:=x1,input_2:=x2,...,input_n:=xn,
  output_1=>y1,output_2=>y2,...,output_n=>yn); 
 
( * internal call of a method of the base function block from within a derived function block *)
SUPER.method-name();
SUPER.method-name
  (input_1:=x1,input_2:=x2,...,input_n:=xn,
  output_1=>y1,output_2=>y2,...,output_n=>yn) 
 
( * external call of a method *)
instance-name.method-name();
instance-name.method-name
  (input_1:=x1,input_2:=x2,...,input_n:=xn,
  output_1=>y1,output_2=>y2,...,output_n=>yn);
Meaning

formal call of the →method without or with a parameter list
The method is called by the name of the method method-name. The specification in front of this name determines in which context the method is called:

  • THIS. – This calls a method of the same language construct. As an alternative, it is also possible to omit THIS. here.
    Example: THIS.UP5(); or UP5(); – This calls the method UP5 e.g. within the method UP. Both methods are declared in the same →function block or in the base function block (if the function block containing the call of the method is a derived function block; see details on the keyword EXTENDS under "Declaration of a function block in ST").

  • SUPER. – This calls a method of the base function block from within a derived function block.
    Example: SUPER.UP5(); – This calls the method UP5 of the base function block. The method is called within a function block that has been derived from a base function block by using the keyword EXTENDS.

  • instance-name. – This calls a method of an →instance.
    Example: Inst1.UP5(); – This calls the method UP5 of the instance Inst1.

No check of recursions

Recursions for →functions and →methods are not forbidden or checked by Neuron Power Engineer. Nevertheless, do not call a function/method from within itself and avoid 2 (or more) functions/methods calling each other (= mutual recursion) within your application. 
Mind that recursions of functions/methods might cause unexpected results when your application is executed. For example, the application might be executed in an infinite loop and/or the →runtime system might not respond anymore.

(info) The possibilities for the parameter list are analogous to the call of a function.

This parameter list of a formal →call may contain the following elements: 

  • →assignments to →input variables (incl. to input EN)
    The expression on the right side of the assignment operator ":=" in the assignments to input variables may be one of the constructs as listed under Assignment.

  • assignments to →in-out variables
    The expression on the right side of the assignment operator ":=" in the assignments to in-out variables may be just a construct which might be on the left side of the assignment operator ":=" as well.

  • assignments of →output variables (incl. to output ENO)
    The expression on the right side of the assignment operator "=>" in the assignments of output variables may be a declared →variable (e.g. result) of a fitting →data type. 

As alternatives, you can use the following variants for the call:

  • non-formal call
    The parameter list must contain the same number of input variables, in exactly the same order and of fitting data types as given in the declaration, except the execution control parameters EN and ENO. 
    Example: Inst1.UP3 (10,20,T#3ms); – This non-formal call is equivalent to the formal call: Inst1.UP3 (EN := TRUE, IN1:=10, IN2 := 20, T1 := T#3ms, OUT => result);

  • incomplete parameter list of formal call
    You can omit input variables and output variables within the parameter list. Omitted input variables get the default →initial value. As previously mentioned, this is analogous to the call of a function (see the examples there.

The FAQ article "When to use a formal call? When to use a non-formal call?" lists a table when to use formal call vs. non-formal call.

An example for an internal call of a method with a parameter list but without EN/ENO is listed under "Declaration of a method".An example for the different calls of methods (using THIS., SUPER. and instance-name.) is listed under "Declaration of a function block in ST".