C/C++ Indexer is not concluded and prevents the saving or importing of an object

Symptom: After saving has been started for an ST-object, the status bar seems to permanently display the information C/C++ Indexer: 94%. This information is still displayed after over 1 hour. Subsequently, it is not possible to edit this ST-object in Neuron Power Engineer anymore.
The same information might be displayed when you are importing the project with this ST-object later on.

Cause: The ST-object contains a statement (e.g. an IF statement) containing a complex â†’expression consisting of more than 20 operands combined e.g. with OR operators.

Example 
IF
  Var1 = 1 OR
  Var2 = 2 OR
  Var3 = 3 OR
  (* and so on *)
  Var30 = 30
  THEN
    Var31 := 100;
END_IF;

Solution: Avoid such complex expressions in order to avoid considerable implications on the performance when saving the ST-object or when importing the project with this object.

Workaround, if the project cannot be imported anymore: Edit the ST-object within a text editor so that the complex expression consists of up to 20 operands/operators only. Then try to import the project anew.