Title: Select a macro application which is a non-legal subexpression
Goal: Generalize the function `f/1' by selecting the expression `?M(3)', the a new parameter is `K'.
Parameters: [{file,"gen19.erl"},{posrange,{63,67}},{varname,"K"}].
Documentation: The selected expression is not a legal subexpression, because after macro substitution the result is the expression `Z-1', and `-1' is not a legal subexpression part of this expression. So the refactoring denied the transformation.
