anchor.diff:  alias_var(Alias) -> cerl:alias_var(Alias).
   alias_pat(Alias) -> cerl:alias_pat(Alias).
   
  +%% Atomic data type functions.
   c_atom(A) -> cerl:c_atom(A).
   ann_c_atom(Ann, A) -> cerl:ann_c_atom(Ann, A).
   c_int(I) -> cerl:c_int(I).
   c_float(F) -> cerl:c_float(F).
   c_nil() -> cerl:c_nil().
   
  +%% Literal value functions.
   ann_c_lit(Ann, Val) -> cerl:ann_abstract(Ann, Val). %Generic literal
   c_lit(Val) -> cerl:abstract(Val).
   is_literal(Node) -> cerl:is_literal(Node).
  
positive.code: ann_c_case(Ann, E, Cs) ->
      cerl:ann_c_case(Ann, E, Cs).
  
  ann_c_clause(Ann, Ps, B) ->                     %Default true guard
      cerl:ann_c_clause(Ann, Ps, B).
  
  ann_c_clause(Ann, Ps, G, B) ->
      cerl:ann_c_clause(Ann, Ps, G, B).
  
  ann_c_seq(Ann, A, B) ->
      cerl:ann_c_seq(Ann, A, B).
  
  
negative.code:     pat_list(Ps, L, Vs, Ts, St);
  pattern([tuple|Ps], L, Vs0, Ts0, St0) ->
      Fun = fun (P, {Vsa,Tsa,Sta}) ->
                    {Cp,Vsb,Tsb,Stb} = pattern(P, L, Vsa, Tsa, Sta),
                    {Cp,{Vsb,Tsb,Stb}}
            end,
      {Cps,{Vs1,Ts1,St1}} = mapfoldl(Fun, {Vs0,Ts0,St0}, Ps),
      {c_tuple(Cps),Vs1,Ts1,St1};
  pattern([binary|Segs], L, Vs, Ts, St) ->
  