Re: Passing variables up to the GUI

[Daniel J Sebald]

On 04/12/2013 08:40 PM, John W. Eaton wrote:
> On 04/12/2013 09:00 PM, Daniel J Sebald wrote:
>
> > For example, I see John just added a new feature for renaming variables
> > in the workspace from the GUI workspace window. That is a nice feature.
> > However, it's done via callback, when it could be done with a command
> >
> > "z = x; clear x;"
> >
> > for example.
>
> If you send commands like this back to the interpreter, I think
> Octave's behavior will seem unreliable and confusing to many users.
> For example, what happens for the above command sequence if there is a
> a variable called "clear" in the top-level workspace? Users will
> expect the buttons on the GUI to always work. Telling them, "if you
> want the GUI to work correctly, then don't define variables with the
> same names as the Octave commands that the GUI uses" doesn't seem very
> good to me.

There is no requirement that such a function behave exactly as the 
interpreter that the user has.  As with the "corefeval" I proposed the 
other day, it is that underlying builtin code that is what the GUI has 
interest in.  So, the commands that go from the GUI's internal access 
bypass that first level of indirection that otherwise would be M-script 
overrides, variable overrides, etc.  Neither would these commands appear 
in the history list.  The best way to describe "corefeval" is that 
builtins cannot be overriden.

Dan