Title: Select a non-legal subexpression
Goal: Generalize the function `f/0' by selecting `2+3', the new parameter `N'.
Parameters: [{file,"gen7.erl"},{posrange,{45,47}},{varname,"N"}].
Documentation: The selected part `2+3' is not a legal subexpression (because the precedence of the operators: ((2*2)+3)), so the transformation is denied.
