Re: An idea: combine-change-calls

[Johan Bockgård]

Stefan Monnier <address@hidden> writes:

>> I'm experimenting with a different strategy: surrounding the mass of
>> elements in buffer-undo-list with a `(combine-change-begin ,beg ,end)
>> and a `(combine-change-end ,beg ,end).
>
> Beware: this changes the format of entries that can appear in the
> buffer-undo-list, which has repercussions beyond primitive-undo, IOW it
> can/will break other things such as undo-in-region and undo-tree.

But the `(apply ...)' forms are a problem for exactly these other
things. It's too powerful. The packages that manipulate buffer-undo-list
can't (and don't try to) handle `apply' properly, since it can contain
arbitrary effects.

> Better use the (apply DELTA BEG END FUN-NAME . ARGS) form, which was
> introduced specifically for use of such extensions.