anchor.diff:  	    {Start, End} = refac_util:get_range(Exp),
   	    case [{S,E}||{S, E}<- GuardRanges, S=<Start, End=<E] of
   		[] -> ok;
  -		_ ->throw({error, "Generalisation of a function application "
  +		_ ->throw({error, "Generalisation over a function application "
   			   "in a guard expression is not supported."})
   	    end;
   	_ -> ok     
  
positive.code:     case Exp_Export_Vars of
  	[_|_] ->
  	    throw({error, "Wrangler does not support generalisation "
  		   "of an expression that exports variables(s)!"});
  	_ -> ok
      end,
      F= fun(Node, Acc) ->
  
negative.code:         {value, {category, record_type}} -> 
  	    throw({error, "Record type cannot be replaced by a variable."});	 
          {value, {category, guard_expression}} -> 
  	    throw({error, "Generalisation over a guard expression is not supported."});
  	{value, {category, application_op}} -> 
  	    GuardRanges=[refac_util:get_range(G) || 
  			    C <-Cs, 
  