free_formula (QuantPred pn pt f) = QuantPred pn' pt' f'
     where pn' = mkFreeName pn
           pt' = free_pred_type pt
           f' = free_formula f
free_formula (QuantPred pn pt f) = QuantPred pn' pt' f'
     where pn' = mkFreeName pn
           pt' = free_pred_type pt
           f' = free_formula f
free_formula (QuantPred pn pt f) = QuantPred pn' pt' f'
     where pn' = mkFreeName pn
           pt' = free_pred_type pt
           f' = free_formula f