anchor.diff:  
   -include("ephp.hrl").
   
  --spec process(Context :: context(), Statements :: [main_statement()]) -> 
  +-spec process(Context :: context(), Statements :: [main_statement()]) ->
       {ok, binary(), return() | false}.
   
   process(_Context, []) ->
  
positive.code: run_depth(Context, #if_block{conditions=Cond}=IfBlock, false) ->
      case ephp_context:solve(Context, Cond) of
      true ->
          run(Context, 
              #eval{statements=IfBlock#if_block.true_block});
      false when IfBlock#if_block.false_block =/= undefined ->
          run(Context, 
              #eval{statements=IfBlock#if_block.false_block});
      _ ->
          false
  
negative.code:         true ->
              run_loop(PrePost, Context, Cond, Statements);
          false ->
              case Break of
                  {return,Ret} -> {return,Ret};
                  _ -> false
              end
          end;
      false ->
  