Re: [rfc] Annotation level THREE

Nick Roberts
2003-03-18T10:31:35Z

> > > Why do you need display-{begin,end}? -display-insert has been made
> > > redundant by the varobj stuff - it lets the GUI efficiently track its
> > > display values outside of the CLI.
> >
> > Variable objects don't auto-display. You seem to have to type
> > -var-evaluate-expression each time the program stops.
>
> Why do you need auto-display? What are you using it for?
>
> Remember, every time the target changes (e.g., from a user modifying a
> variable or register), the display needs to be updated. This is because
> that variable/register has the potential to modify every single value
> being displayed. Further, unless your using some sort of changes-only
> mechanism, such as provided by the varobj, the display windows are just
> not going to scale.

You're right. If the user assigns a value to a variable, using my code, the
display window for that variable won't update in Emacs until the next
statement is executed.

What do you mean by `not going to scale'? Currently if I display an array
slice, say just a few elements from a large array, I need to parse them from
output for the whole array. Could I arrange for GDB to just output the elements
I want using variable objects?

Can I get GDB to tell me what the current list of variable objects is? Can
I generate names for them automatically?

> > > The testsuite is a good source of
> > > varobj examples (unfortunatly lacking from the doco):
> > > http://sources.redhat.com/gdb/current/onlinedocs/gdb_25.html#SEC565
> >
> > The lack of documentation for (and apparent completeness of) GDB/MI is part of
> > the problem.
>
> Um, the varobj is documented. It just lacks a vew concrete examples.
> Those can be found by examining the testsuite. Both Apple and Eclipse
> are using this part of the MI.

Its a question of resources. I'm one person doing things in my spare time.
Apple and Eclipse have full time teams dedicated to the task.

> > > The above list also contains thing like field-{begin,end},
> > > array-section-{begin,end} et.al. Why are they needed.
> >
> > I use them to parse the output. They could probably go, if necessary, but
> > others that you plan to take out *are* needed.
>
> Can you please be more specific?

Perhaps I could turn that question round. Which annotations are you planning
to keep?

Nick