On Thu, Oct 17, 2019 at 8:02 PM Stefan Monnier <monnier@iro.umontreal.ca>
wrote:
>
> Just to be clear: this is a typical bikeshed subject.

Definitely.

> So far, AFAIK most of the code and docstrings use nil/non-nil, AFAICT
> (which is why we're all familiar with the notion of "non-nil" as
> a matter of fact) and as a maintainer I've made an effort to try and
> standardize on this, e.g. by fixing docstrings which overspecified the
> return value to `t`.

There's a cascading effect. Some functions with multiple non-nil return
values rely on other functions's declared boolean result to construct their
own. So I think functions that can only return a boolean are not
"overspecified" by saying so. YMMV.

> The most important thing is to try and choose one and stick to it, both
> for the benefit of consistency and to avoid back-and-forth
> cosmetic changes.

FWIW, I don't consider making a function return what its docstring says "a
cosmetic change".