anchor.diff:  ]).
   
   
  -
   %%=============================================================================
   -spec b2l(binary()) -> list().
   b2l(Bin) ->
  
positive.code: 
  %%=============================================================================
  -spec ext_req(Key, Req) -> {any(), any()} when
    Key :: term(),
    Req :: proplists:proplist().
  ext_req(Key, Req) ->
    case proplists:lookup(Key, Req) of
      none -> {Key, <<>>};
      Tuple -> Tuple
    end.
  
  -spec ext_req(Key, Req, DefaultValue) -> {any(), any()} when
    Key :: term(),
  
negative.code:     Tuple -> Tuple
    end.
  
  ext_req_test() ->
    ?assertEqual([{a, 1}, {b, 2}],
      ext_req([<<"a">>, <<"b">>]
        , [{<<"a">>, 1}, {<<"b">>, 2}])),
    ok.
  %%=============================================================================
  -spec try_ext_req(Key, Req) -> {any(), any()} when
    Key :: term(),
    Req :: proplists:proplist().
  