[erlang-questions] why doesn't this dbg example work?

[Leo Liu]

Hi there,

In dbg's reference manual, there is this example, which I cannot
replicate:

    (x@REDACTED)4> dbg:tp(lists,sort,cx).
    {ok,[{matched,nonode@REDACTED,2},{saved,cx}]}
    (x@REDACTED)4> lists:sort([2,1]).
    (<0.32.0>) call lists:sort([2,1]) ({erl_eval,do_apply,5})
    (<0.32.0>) returned from lists:sort/1 -> [1,2]
    [1,2]

My shell session:

    (devel@REDACTED)1> dbg:tracer().
    {ok,<0.2100.0>}
    (devel@REDACTED)2> dbg:tp(lists, sort, cx).
    {ok,[{matched,devel@REDACTED,2},{saved,cx}]}
    (devel@REDACTED)3> lists:sort([2,1]).
    [1,2]

Note there are no trace outputs in my shell session. Ideas?

Thanks,
Leo