Maxima has work-arounds for all these issues built in and I am used to them so I don't see any need to make a massive
rewrite just so to do this.
You can do this.
(%i1) x:10;
(out1) 10
(%i2) diff('x^2,'x);
(out2) 2 x
(%i3) diff(x^2,x);
diff: second argument must be a variable; found 10
-- an error. To debug this try: debugmode(true);
(%i4)
Rich
--------------------------------------------------
From: "Dieter Kaiser" <drdieterkaiser at web.de>
Sent: Tuesday, February 23, 2010 3:15 PM
To: "Raymond Toy" <toy.raymond at gmail.com>
Cc: "Stavros Macrakis" <macrakis at alum.mit.edu>; <maxima at math.utexas.edu>
Subject: Re: [Maxima] $asksign might need its own context
> Am Dienstag, den 23.02.2010, 14:45 -0500 schrieb Raymond Toy:
>> On 2/23/10 11:07 AM, Stavros Macrakis wrote:
>> > Maxima's intended behavior is that every %i/%o interaction is an
>> > asksign domain. If you want isolated environments within that, you
>> > need to create them explicitly.
>> I guess that makes some sense. It's easily explained and is probably
>> what people want.
>>
>> But I think I agree with Robert. After evaluating those integrals, I'm
>> not sure I would want maxima to think that a = -1 for ever after. On a
>> second reading of Dieter's message, I'm not sure that's what he's
>> saying. Perhaps he meant for maxima to remember just for that one
>> expression; it's not clear to me because I don't understand these
>> context things.
>>
>> But having maxima ask just one question for the expression is pretty good.
>
> Hello Ray,
>
> to be more clear.
>
> The context for the facts of asksign is only present during one
> evaluation with meval*. The facts are killed after the evaluation with
> meval*. This is the design we have and I think this design is useful for
> the user, because it does not make sense to answer again and again
> redundant questions.
>
> I have not intended to change this behavior, but to implement it more
> strong.
>
> Dieter Kaiser
>
>
> _______________________________________________
> Maxima mailing list
> Maxima at math.utexas.edu
> http://www.math.utexas.edu/mailman/listinfo/maxima
>