[GiNaC-list] sympy and a derived work

[Ondrej Certik]

Dear Richy,

> Good heavens. Let's not try to quantify this "free" thing too much,
> please. At the ICMS'2006 in Spain, someone started exactly the same
> discussion at the end of my talk about CLN: Some people really do
> believe that if you put your software under a BSD, LGPL, or MIT style
> license, then the entire closed-source software industry will
> miraculously be turned into saints and start helping your project by
> contributing code, doing the debugging for you, organizing events,
> giving you free lunch, etc.

I don't belong among people believing in that. One should use GPL,
or some other copylefted license for that.

> That is just so naive. At the ICMS'2006, the GMP (LGPL) developer
> explained in response, how much feedback he ever got back from Wolfram
> Research who ship libgmp with Mathematica: absolutely no feedback. Zero,
> vacuum, null, rien, nada, nix. There was a Wolfram employee in the room
> then, and I don't really know if the situation has changed since but I
> wouldn't bet it has.

Yep. One shouldn't blame Wolfram for that though, but those who
made GMP LGPL and now cry (if they cry).

> Oh, and interestingly, at the end of the old argument why CLisp is GPL
> you'll find someone foreseeing this problem with GMP:
> <http://cl-debian.alioth.debian.org/repository/pvaneynd/bzr-moved/clisp/doc/Why-CLISP-is-under-GPL>
> (CLN wasn't around at that time. But it borrows enough code from CLisp
> so that this argument applies to it, too. In the end, it's not
> far-fetched to argue that this decision set the course for GiNaC's license.)

Right.

> If you pick another license, that's fine. But, please, be careful not to
> offend other open-source developers who, by choice or by necessity, made
> a different pick.

I am sorry if I offended you.

> > However, we now changed almost everything in sympy,
> > just the class structure stayed - but I mean - it's just a class structure
> > (even that is not 100% the same, we don't use ex for example).
> >
> > So I wanted to clarify with you, if it's ok, if we use BSD for sympy.
>
> Ondrej, you're going to have fun if you are seriously bringing this up.
>
> IANAL, but you are obviously raising two questions: Is SymPy derived
> work of GiNaC? Personally, I do not know or care (but don't know about
> other contributor.) If *you* think it is, then, you must now clarify the
> situation with the copyright holder for GiNaC. According to the source
> files, that would be the University of Mainz, Germany. Please, do keep
> us posted about what comes out from the discussion with their lawyers,
> okay? Because I don't think they are reading this list.  ;-)

I personally don't think SymPy is a derived work, so I am not going
to do any actions. I however respect copyrights and licenses, but I am
not a lawyer and I don't intend to become a lawyer, so I have just brought
it to your attention, since you or other GiNaC developers may have other
opinion on this than I do.

Ondrej