Re: RFC on bug #3672: pretty printing compound types

[Josh Stone <jistone at redhat dot com>]

On 05/28/2010 06:33 PM, Frank Ch. Eigler wrote:
>> [...]  The other idea that I'm favoring is to stop following
>> pointers, and just make "$" print the structure without any
>> substructures and "$$" print with all substructures.  [...]
> 
> In that case, we'd have no primitive for following generic pointers,
> right?  So one would have to hand-write scripts like these in order to
> draw to pointed-to structures.
> 
> # probe process("stap").function("*::visit_target_symbol")
> #   printf("%s  %s\n", $e$, probefunc())
> or 
> #   printf("%s  %s\n", $e->tok$, probefunc())
> 
> That seems unfortunate.  Maybe use your arrow notation to indicate
> pointer-dereferenced pretty-printing?
> 
>     $e->->$   for two levels of pointer dereferncing?

It quickly blows up in size when you traverse pointers though, and we're
limited to MAXSTRINGLEN.  I have no generic way to know that ->tok is
the only pointer you care about, so all the other pointers in the
structure get expanded too.

Would it be ok if I just make the suggested change now, and then later
we can consider introducing the arrow notation to expand further?


Josh