Re: Technically correct or conceptually easier?

[chad <yandros@gmail.com>]

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As a practical matter, could this specific instance be addressed by
something like "...if the value is a (non-nil) list, ...."?

On Thu, Apr 2, 2020 at 2:22 PM Stefan Monnier <monnier@iro.umontreal.ca>
wrote:

> > The first sentence of the documentation says:
> >
> >   Non-nil means disregard read-only status of buffers or characters.
> >
> > OK.  And what nil means?  I guess the omission of its meaning implies
> > its meaning is the exact opposite of the one given to a non-nil value;
> > and apparently this conjecture can be factually verified by
> > experimentation.
>
> Yes, we often rely on the abuse of "if" to mean "if and only if".
> Usually those abuses allow for less verbose text, so there's
> a trade-off.  I think here the trade-off is worthwhile.  At some other
> places we correctly add an explicit mention of what happens if it's nil.
> And of course at yet other places we made the wrong call :-(
>
> >   If the value is a list, disregard ‘buffer-read-only’ and disregard a
> >   ‘read-only’ text property if the property value is a member of the
> >   list.
> >
> > Well, nil is a list.
>
> I think this case is a documentation error: it should say "a non-empty
> list", although admittedly, the context makes it clearish what is meant.
>
>
>         Stefan "who likes `iff`"
>
>
>

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