bug#12685: 24.2; lexical binding breaks edebug conditional breakpoints

[Stefan Monnier]

>> The fact that it aborts execution should be fixable before the release
>> (tho I'm not sure that it's really better to silently mis-interpret the
>> user's request),
> Indeed.  But that's what the documentation says it should do, so either
> the documentation or the implementation needs to be changed so that they
> at least match.

I think at this stage the best is to add a note that it might fail when
used for lexical-binding code.

> I figured as much. Maybe for now we could mention in the Edebug section
> of the Elisp manual which parts of edebug won't (currently) work in
> lexically-scoped code? As far as I can see, M-: and conditional
> breakpoints should be the only things that are affected. (Though
> `edebug-step-in' doesn't always seem to work for me lately, but I can't
> reliably reproduce this at the moment.)

Agreed.  Could you take care of it?

> Maybe the docs should even recommend disabling lexical-binding when
> edebugging for now.

I don't think so.  The programmer can reach his own conclusion based on
the text you'll add warning that some parts don't work.

> (Is there a good way of configuring this to happen
> automatically?

No, that would be even worse, since some code only works in
lexical-binding mode (and there's no way to figure out if the code in
the current buffer is in this category).


        Stefan