Re: beginnings of Guile support

[Tom Tromey <tromey@redhat.com>]

>>>>> "Doug" == Doug Evans <dje@sceeck.org> writes:

Doug> As a personal project, I'm adding scheme scripting to gdb.

I'd rather not put this in.  I think multiple scripting languages
fragments the user community and leads to hard-to-debug problems.

It also requires difficult cross-language integration.  Your patch skips
the hard bits, but I think that is cheating -- those have to be fixed
first.

Doug> To try to plug scheme in cleanly I've created scripting.[ch] as
Doug> the interface between gdb and python/scheme.

The current interface uses "slang" as a name, but that is the name of an
existing scripting language.  I think another name would be preferable
in case someone wants to add slang scripting.

Doug> +slang_sourcer_func *
Doug> +get_slang_sourcer (const char *file)
Doug> +{
Doug> +  if (has_extension (file, ".py"))
Doug> +    {
Doug> +#ifdef HAVE_PYTHON
Doug> +      return python_scripting_interface.source_script;
Doug> +#else
Doug> +      return source_python_unsupported;
Doug> +#endif

I think there are too many #ifs of this form.
It means the abstraction is incomplete.

Doug>  /* Variables used to pass information between the Breakpoint
Doug>     constructor and the breakpoint-created hook function.  */
Doug> -breakpoint_object *bppy_pending_object;
Doug> +gdbpy_breakpoint_object *bppy_pending_object;
 
Renamings ought to be separate patches.

Doug> -/* Helper function that overrides this Python object's
Doug> -   PyObject_GenericSetAttr to allow extra validation of the attribute
Doug> -   being set.  */
Doug> -
Doug> -static int 
Doug> -local_setattro (PyObject *self, PyObject *name, PyObject *v)
Doug> -{
Doug> -  breakpoint_object *obj = (breakpoint_object *) self;  
[...]

I'm not sure why this was deleted, but it also seems like it ought to be
a separate patch, or maybe dropped.

Doug> +/* INCOMPLETE TODO LIST:

I skimmed the guile code, but didn't read it heavily.

I think anything that calls into Guile from gdb ought to prevent
continuation capture.  Otherwise madness will ensue.  I don't know how
you do that in Guile but I didn't see anything obvious in the code.

Tom