Re: [PATCH 01/12] libxc/save: Shrink code volume where possible

[Ian Jackson <ian.jackson@xxxxxxxxxx>]

Andrew Cooper writes ("Re: [PATCH 01/12] libxc/save: Shrink code volume where 
possible"):
> On 14/01/2020 16:48, Ian Jackson wrote:
> > Andrew Cooper writes ("[PATCH 01/12] libxc/save: Shrink code volume where 
> > possible"):
> >> A property of how the error handling (0 on success, nonzero otherwise)
> >> allows these calls to be chained together with the ternary operatior.
> > I'm quite surprised to find a suggestion like this coming from you in
> > particular.
> 
> What probably is relevant is that ?: is a common construct in the
> hypervisor, which I suppose does colour my expectation of people knowing
> exactly what it means and how it behaves.

I expect other C programmers to know what ?: does, too.  But I think
using it to implement the error monad is quite unusual.  I asked
around a bit and my feeling is still that this isn't an improvement.

> > Or just to permit
> >    rc = write_one_vcpu_basic(ctx, i);    if (rc) goto error;
> > (ie on a single line).
> 
> OTOH, it should come as no surprise that I'd rather drop this patch
> entirely than go with these alternatives, both of which detract from
> code clarity. The former for hiding control flow, and the latter for
> being atypical layout which unnecessary cognitive load to follow.

I think, then, that it would be best to drop this patch, unless Wei
(or someone else) disagrees with me.

Sorry,
Ian.