[chirp_devel] Parameterized memory maps

[Brian Dickman]

Thanks for the feedback Dan. I'm going to opt for named formatters but
I'll keep it as straightforward as possible. I thought about
overloaded fixed-string names but that would still mean I'd have to
add more conditionals or class-based overloads of get_memory(). By
using formatters I can keep the decoded memory attribute names the
same between 2 models, and the parent class function can be used
without any overload in the inherited class.

--
Brian

On Thu, Sep 1, 2016 at 7:10 AM, Dan Smith <dsmith at danplanet.com> wrote:
>> I'm working on adding Leixen VV-898S support. They decided to take
>> what used to be 1 bit for Power and 1 bit for Mode and instead use
>> both bits for Power, and move Mode to a previously unused bit. I could
>> work around this by parameterizing the map, so it would look sorta
>> like this:
>>
>> u8 %s:1,
>>      foo1:1,
>>      foo2:1,
>>      foo3:1,
>>      foo4:1,
>>      foo5:1,
>>      %s;
>>
>> The first radio would format it as:
>>
>> MEM_FORMAT % ( 'unknown' , 'mode:1,power:1' )
>>
>> while the second would format it as:
>>
>> MEM_FORMAT % ( 'mode' , 'power:2' )
>>
>> Any fundamental objections to this approach? Should I just suck it up
>> and combine the bits at read time on the second radio instead of
>> parameterizing?
>
> We've done this before in places. I do think we should use it sparingly
> as it's confusing. The places we've used it before have mostly been
> around setting an offset for a "#seekto %i" kind of thing.
>
> So, if it's massively harder to do it without the parameter bit then
> it's probably worth it. If not, I'd rather just do something like:
>
>  u8  powerormode:1
>      ...
>      newpower:1;
>
> and just handle the switch in code depending on the model. I just figure
> it's easier to read and debug later for someone that doesn't know what
> is going on. Just MHO though.
>
> If you're going to do something like what you describe, it would
> probably be good to use named parameters so that it's easier to figure
> out which one is which, instead of just by counting:
>
>  MEM_FORMAT = """
>     u8 %(powerormode)s:1,
>        ...
>        %(newpower)s:1;
>  my_format = MEM_FORMAT % {'powerormode': 'power',
>                            'newpower': 'unknown'}
>
> ...or something.
>
> --Dan