Re: Errors in interactive commands

[Stefan Monnier <monnier@iro.umontreal.ca>]

>> Examples such like this one is why I propose using something like
>> (throw 'command-level) instead of raising an error.
> How would that change anything, apart from breaking code that tries to
> catch the error?  Raising an error throws to top-level by default
> anyway.

Exactly.  I think signalling errors is not a bad approach, tho it should
be improved to use `user-error' rather than just `error' for cases which
are normally associated with user errors (which are usually listed in
debug-ignored-errors).  This way we won't need as many regexps in
debug-ignored-errors.

As for the difference between signalling errors and returning nil, they
are fundamentally equivalent, so it's really a question of which is more
convenient "in typical cases".
More consistency would be good, but since any changes in this area risk
introducing backward compatibility problems, I'm strongly in favor of
leaving things as they are.


        Stefan