anchor.diff:  %% lc_tq(Line, Exp, [Qualifier], Mc, State) -> {LetRec,[PreExp],State}.
   %%  This TQ from Simon PJ pp 127-138.  
   
  -lc_tq(Line, E, [#igen{anno=GAnno,acc_pat=AccPat,acc_guard=AccGuard,
  +lc_tq(Line, E, [#igen{anno=GAnno,ceps=Ceps,
  +		      acc_pat=AccPat,acc_guard=AccGuard,
                         skip_pat=SkipPat,tail=Tail,tail_pat=TailPat,
                         arg={Pre,Arg}}|Qs], Mc, St0) ->
       {Name,St1} = new_fun_name("lc", St0),
  
positive.code:                                 ann_c_cons(LA, Skip, Tail)}
                         end,
      {Ce,Pre,St4} = safe(E, St3),
      Gen = #igen{anno=#a{anno=GA},acc_pat=AccPat,acc_guard=Cg,skip_pat=SkipPat,
                  tail=Tail,tail_pat=#c_literal{anno=LA,val=[]},arg={Ceps++Pre,Ce}},
      {Gen,St4};
  generator(Line, {b_generate,Lg,P,E}, Gs, St0) ->
      LA = lineno_anno(Line, St0),
  
negative.code: 			    args=[Sz]}}] ++ BcPre,
      {E,Pre,St}.
  
  bc_tq1(Line, E, [#igen{anno=GAnno,ceps=Ceps,
  		       acc_pat=AccPat,acc_guard=AccGuard,
                         skip_pat=SkipPat,tail=Tail,tail_pat=TailPat,
                         arg={Pre,Arg}}|Qs], Mc, St0) ->
      {Name,St1} = new_fun_name("lbc", St0),
  