anchor.diff:  	t_update_map_expressions/1,
   	t_update_assoc/1, t_update_assoc_large/1,
           t_update_exact/1, t_update_exact_large/1,
  +        t_update_deep/1,
   	t_guard_bifs/1, t_guard_sequence/1, t_guard_update/1,
   	t_guard_receive/1, t_guard_fun/1,
   	t_list_comprehension/1,
  
positive.code: 
      ok.
  
  
  t_guard_bifs(Config) when is_list(Config) ->
      true   = map_guard_head(#{a=>1}),
  
negative.code: 	t_update_map_expressions,
  	t_update_assoc, t_update_assoc_large,
          t_update_exact, t_update_exact_large,
          t_update_deep,
  	t_guard_bifs, t_guard_sequence, t_guard_update,
  	t_guard_receive,t_guard_fun, t_list_comprehension,
  	t_map_equal, t_map_compare,
  