1signature numContext = 2sig 3 4 type subtype_context_element = subtypeTools.subtype_context_element 5 type precontext = subtypeTools.precontext 6 type context = subtypeTools.context 7 8 (* Subtype checking *) 9 val num_sc : subtype_context_element list; 10 11 (* Contextual rewriting *) 12 val num_pc : precontext; 13 val num_c : context; 14 15end 16 17