Re: more on exceptions; new handler

[Paul Kienzle]

On Fri, Nov 15, 2002 at 09:23:12AM -0600, John W. Eaton wrote:
> | This leads to another question, which is whether or not it is feasible
> | to implement evalin, which allows a function to evaluate a variable in
> | the caller's environment.  Not that I particularly need this feature.
> 
> Yes, I think we can implement evalin.  I think that was already
> possible, even without using C++ exception handling?

I didn't see a way of retrieving the symbol table of the caller.  It is
in the unwind stack as defined in ov-usr-fcn.cc:

        unwind_protect_ptr (curr_sym_tab);

but unless I want to walk the unwind stack looking for it, the value is
unavailable:

        curr_sym_tab = sym_tab;

evalin("base") is possible since that is just top_level_sym_tab, but 
not evalin("caller").

- Paul