Re: Lisp primitives and their calling of the change hooks

[Stefan Monnier]

> What do other primitives do when there's an error?

They follow the same rules, AFAIK (e.g. they may for example call b-c-f
and nothing else if no modifications were performed).

> Up front, I see no reason to keep any promises when that happens.

We should still obey the general rules about b-c-f and a-c-f.

>> The (1 22016) b-c-f is thus unbalanced when this happens.
> If this is really important (and I don't see why it would be),

Indeed, it doesn't look like a problem.

> Is implementation convenience the only argument for Stefan's variant?

Not just convenience but also "obviously correct", i.e. more maintainable.


        Stefan