Re: commSetTimeout looks odd.. maybe

[Alex Rousskov]

On Tue, 2008-04-08 at 22:38 +0200, Henrik Nordstrom wrote:
> in commSetTimeout there is the following fragment which looks very odd
> to me
> 
>         if (callback != NULL) {
>             typedef CommTimeoutCbParams Params;
>             Params &params = GetCommParams<Params>(callback);
>             params.fd = fd;
>             F->timeoutHandler = callback;
>         }
> 
> Does this do anything?
> 
> If it does, is this really the proper way? That params variable is only
> junk, right?

> I guess it actually does something, with params being a reference..

Yes, it is setting the fd member of the call[back].

You will find this style throughout the comm module. Since calls have to
support old-style function pointer calls and new-style method calls, and
since they can call any object or function, you cannot get from the
generic call pointer to comm-specific parameters without some casting.

The syntax may improve a little once/if we drop support for old-style
function pointer calls (I am not sure we will), but I think it is not
too bad. Is it?

Thanks,

Alex.
P.S. The params reference is not needed, especially when you set just
one member, but I think it makes things more clear and makes similar
code look similar, regardless of the number of data members being set.