Re: Discrepancy between Python and Guile wrt exiting the interpreter

[Pedro Alves <palves@redhat.com>]

On 1/18/20 11:07 AM, Eli Zaretskii wrote:
> If you invoke the Guile interpreter from GDB:
> 
>   (gdb) gr
> 
> then typing ,q followed by Enter exits the Guile interpreter back to
> GDB.  However, if the Python interpreter is started:
> 
>   (gdb) pi
> 
> then typing quit() and Enter exits GDB, not just the Python
> interpreter.  Why do these two interpreters behave differently in this
> context?  Is there some other Python command to exit the interpreter?
> (I know about Ctrl-D, but I'm asking about commands.)
> 

Note that these commands are not direct equivalents.  The guile equivalent
to "pi" which is short for "python" would be "guile", or "gu", and with
that command you get the same behavior as "pi", in the sense that ",q"
doesn't bail you out, you have to type some command and finish with
either Ctrl-D or Ctrl-C to abort.

"gr" is an alias for "guile-repl", and with that command, it's the Guile
repl that implements the ",q", not GDB.  With the "python" and "guile"
commands, it's GDB that implements the secondary prompt handling and
command line reading (the ">", etc.).  Compare guile_repl_command and
guile_command.

I think that calling quit() in the Python interpreter ends up being the
the equivalent of doing:

 (gdb) guile
 > (primitive-exit)
 Ctrl-D

Thanks,
Pedro Alves