Mercurial in pure Java

[Theodore Tso]

On Thu, Oct 01, 2009 at 01:02:59PM -0700, cbcurl wrote:
> 
> > >> You are talking about "technical ideas". Ideas are not copyrighteable.
> >
> > > No, but API's are. You cannot legally implement hg's API without
> > > honoring its license.
> >
> > In the US at least, I don't think so, since you can't copyright
> > functionality:http://www.eetimes.com/news/design/showArticle.jhtml?articleID=201801579
> >
> > I doubt it is different in Europe.
> 
> That's good. Does this extend to the command set as well?

Not in the United States.  See:

	http://progfree.org/Copyright/copyright.html

Note that the League for Programming Freedom and the Free Software
Foundation called boycotts against Lotus Software while the court case
was being decided, and that both the LPF and the FSF stated position
on Interface Copyrights is that they are Evil.  That's because to the
extent that the FSF has implemented programs that replace Unix
programs --- like gawk, bison, ls, rm, etc., --- if copyright extended
to interfaces, it would apply to coreutils, gawk, sed, glibc, etc.
Fortuntaely, it doesn't.

I'll note also that the command set for hg, bzr, and git all look very
similar to each other, and to predecessor systems, such as BitKeeper.
And no, that's not a copyright problem either.

<Sigh>

						- Ted