Re: Robustifying pretty-printers

[Tom Tromey <tromey@redhat.com>]

>>>>> "Vladimir" == Vladimir Prus <vladimir@codesourcery.com> writes:

Tom> -var-set-child-range 10 20
Tom> -var-list-children

Vladimir> And what children with -var-update reevaluate? From 10 to
Vladimir> 20? Or from 0 to 20? If the former, it's not very useful. If
Vladimir> the latter, then it appears that low boundary is only used
Vladimir> for -var-list-children.

Right.  There is a separation between what the varobj code does
internally, and what MI reports to the FE.

-var-set-child-range affects what is reported to the FE.  Only
children in that range are reported.  I was assuming the same would be
true even if this were done via arguments to -var-list-children.

What happens in varobj is another matter.  Currently we always fetch
children starting at 0, because the pretty-printers have a simple,
iterator-based design.

Vladimir> Maybe, it's most useful to decouple setting the range for -var-update
Vladimir> and getting specific children. So, if frontend wants more children
Vladimir> now, it will do:

Vladimir> 	-var-list-children 10 20

Vladimir> and if it wishes for 20 children to be fetched from now on, it will
Vladimir> explicitly do:

Vladimir> 	-var-set-child-limit 20

What is the difference between this and "-var-list-children 0 20"?

Tom