anchor.diff:  
   eval_apply_expr(Func, Es, Env) ->
       case lfe_macro:expand_expr_all(Func, Env) of
  -    [lambda,Args|Body] -> apply_lambda(Args, Body, Es, Env);
  -    ['match-lambda'|Cls] -> apply_match_clauses(Cls, Es, Env);
  -    Fun when erlang:is_function(Fun) -> erlang:apply(Fun, Es)
  +        [lambda,Args|Body] -> apply_lambda(Args, Body, Es, Env);
  +        ['match-lambda'|Cls] -> apply_match_clauses(Cls, Es, Env);
  +        Fun when erlang:is_function(Fun) -> erlang:apply(Fun, Es)
       end.
   
   %% eval_if(IfBody, Env) -> Value.
   
  -eval_if([Test,True], Env) ->            %Add default false value
  +eval_if([Test,True], Env) ->                    %Add default false value
       eval_if(Test, True, [quote,false], Env);
   eval_if([Test,True,False], Env) ->
       eval_if(Test, True, False, Env).
   
   eval_if(Test, True, False, Env) ->
       case eval_expr(Test, Env) of
  -    true -> eval_expr(True, Env);
  -    false -> eval_expr(False, Env);
  -    _ -> erlang:error(if_clause)        %Explicit error here
  +        true -> eval_expr(True, Env);
  +        false -> eval_expr(False, Env);
  +        _ -> erlang:error(if_clause)            %Explicit error here
       end.
   
   %% eval_case(CaseBody, Env) -> Value.
  
positive.code: -module(lfe_eval).
  
  -export([expr/1,expr/2,gexpr/1,gexpr/2,apply/2,apply/3,
       body/1,body/2,guard/1,guard/2,
       make_letrec_env/2,add_expr_func/4,match/3,match_when/4]).
  
  %% Deprecated exports.
  -export([eval/1,eval/2,eval_list/2]).
  
negative.code: 
  eval_case_clauses(V, Cls, Env) ->
      case match_clause(V, Cls, Env) of
          {yes,B,Vbs} -> eval_body(B, add_vbindings(Vbs, Env));
          no -> erlang:error({case_clause,V})
      end.
  
  match_clause(V, [[Pat|B0]|Cls], Env) ->
  