anchor.diff:  
               From ! {Ref, Reply },
               %% Return state with options and any non-duplicate original opts.
  -            NSt1#st {  
  -              opts = Opts1 ++ 
  +            NSt1#st {
  +              opts = Opts1 ++
                 [{K,V} || {K,V} <- St#st.opts, not lists:keymember(K,1,Opts1) ]
                };
   
  -        {timeout, _TRef, sample} ->
  +        {timeout, _TRef, {exometer_proc, sample_timer}} ->
               sample(St);
   
           {exometer_proc, delete} ->
  
positive.code: %%  If the data can be collected at a high speed, and without
  %%  blocking, an `exometer_entry' implementation can be used instead
  %%  to do the gathering in-process.
  %%  
  %%  A probe is created throgh the `exomter_probe:new/3' call, which in
  %%  its turn is called by `exometer:new/3'. During probe creation, a
  %%  new process is spawned to handle the probe and call its
  
negative.code: %%  call, which specifies the data points to be returned. The probe is
  %%  expected to gather the given data points and return them to the
  %%  caller.
  %%
  %% == The probe callback interface ==
  %%
  %% The following functions are to be implemented and exported by a probe
  %% implementation.
  %%
  %% === behaviour/0 ===
  %%
  %% The `behaviour/0' function for an entry implementation should return
  %% the atom `probe'. This function will be involved by the
  %% exometer system in order to determine if a callback is
  %% an entry or a probe.
  %%
  %% === probe_init/3 ===
  %% The `probe_init/3' function is invoked as follows:
  %%
  %% <pre lang="erlang">
  %%      probe_init(Name, Type, Options)</pre>
  %%
  %% The implementation shall initiate the probe, create the
  %% necessary state, and return it for furure access
  %% through `probe_update/2', `probe_sample/1' and `get_value/2' calls.
  %%
  %% The arguments are as follows:
  %%
  %% + `Name'
  %%     Specifies the name of the metric to be created as a list of atoms.
  %%
  %% + `Type'
  %%     Specifies the type provided to the `exometer:new/3' call (before it
  %%     was translated by the type - exometer probe map). It can be used if several
  %%     different types are mapped to the same probe module.
  %%
  %% + `Options'
  %%     Specifies an option list that contains additional setup directives to
  %%     the probe. The actual options to support are a combination of the
  %%     standard options, described below, and probe specific options
  %%     processed by `probe_init/3'.
  %%
  %% Standard options are processed directly by `new/3', before
  %% `probe_init/3' is calledm and are as follows:
  %%
  %% + `{priority, P}'
  %%     Will be forwarded by the probe's process to `erlang:process_flag/2'.
  %%
  %% + `{min_heap_size, S}'
  %%     Will be forwarded by the probe's process to `erlang:process_flag/2'.
  %%
  %% + `{min_bin_vheap_size, S}'
  %%     Will be forwarded by the probe's process to `erlang:process_flag/2'.
  %%
  %% + `{sensitive, true | false}'
  %%     Will be forwarded by the probe's process to `erlang:process_flag/2'.
  %%
  %% + `{sample_interval, t}'
  %%     Specifies the interval, in milliseconds, that `erlang:process_flag/2'.
  %%     should be invoked at.
  %%
  %% The `probe_init/3' implementation is invoked by `exometer:new/3',
  %% which calls `exometer_probe:new/3', which invokes the probe
  %% implementation..
  