Checking variable scope

["Rob Quill" <rob.quill@gmail.com>]

On 28/11/06, Jim Blandy <jimb@codesourcery.com> wrote:
>
> "Rob Quill" <rob.quill@gmail.com> writes:
> > The aim would be to add a command to gdb, in_scope (or similar) which
> > can be used from a GDB script to check if a variable is in scope
> > without throwing an error if is isn't. As currently if I do "print a"
> > and a is not in scope then I get an error and the script stops, which
> > is fine. But even better would be if I were able to check if a was in
> > scope and only print (or do other things with it) if it was.
>
> Why don't you add a new expression operator, $in_scope(a), which
> evaluates to zero or one?  You could just imitate the other code in
> the parser and expression evaluator, so this should be straightforward
> to implement, and then you could use it in GDB script conditional
> commands.
>

Could you elaborate on this a bit please? I'm not really sure what you
mean and how to go about implementing it.

Thanks,
Rob