Re: Errors in interactive commands

[Stephen J. Turnbull]

Andreas Röhler writes:

 > Useful return values of "forward-" is important for a wide range of 
 > things, not just to serve several specific cases.

Unfortunately, when there are "several specific cases", they often
have different requirements.  Your term "useful" is undefined, and you
need to define it and show that there is a unified definition powerful
enough to make it worthwhile to introduce a backward-incompatible
change.

One way to present such definitions is to describe use cases.  Mine is
an important one: "iterating over a presumed-to-be array-structured
buffer, executing a destructive action on each element of the structure."

On the other hand, your pseudo-code is way too "pseudo" to be useful
to me.  Please *define* the functions that check and update
"delete-second-state".  I think you will find it is rather hard to do
as efficiently as my code, without duplicating my code (perhaps
implicitly).