Re: adding support for ptype to MI

[Dodji Seketeli <dseketel at redhat dot com>]

Keith Seitz wrote:

> I'm afraid I don't understand what the problem is. Varobj certainly 
> provides a hierarchical view of variables, and that includes type 
> information.
>
> Is that developers want just type information (e.g., for a type 
> browser/inspector kind of thing)? In which case I would expect 
> "-var-create - * (TYPE)0" to work. Alas, I see that is now broken.

There are times where you don't necessarily want to resort to varobjs.

For instance, if I can parse the result of "-data-evaluate-expression 
<variable-name>" _quickly enough_, using it incurs less latency than 
using varobjs. At the end of that, that results into a snappier UI for 
the user. And to me, that's a feature.

Also, as varobjs have to be managed per frame - you have to delete them 
when you leave a frame and that obliges you to send MI commands each 
time you enter a new frame anyway - they obliges the client to do book 
keeping. At least in the current versions of GDB that are shipped on 
most distros.

So quickly doing -data-evaluate-expression <variable-name> does have its 
need. Similarly, the hypothetical -data-print-type <variable-name> that 
I'd like to see has its need as well.

I am not saying that varobjs are useless. But I think being able to 
print the type of a variable, fully, and get the result as a serialized 
object can be very very useful.

Cheers,

Dodji.