Re: Lilypond \include statements and the GPL

[David Kastrup]

Joseph Rushton Wakeling <address@hidden> writes:

> Hello all,
>
> A question which has come up, and where I'm not sure what the answer or
> intention is.
>
> Lilypond is licensed under the GPL and reading through the license file, I
> didn't come across any granted exceptions (IIRC the fonts have an exception 
> for
> embedding them into a document).
>
> So, how does this affect things when e.g. you \include a file in your
> personal Lilypond project?  While I can't see it affecting
> distribution of a PDF or other graphical version of the score
> produced, the lack of an exception surely means that any .ly file
> distributed would be obliged to be released under the GPL or a
> compatible license.

I don't see that.  \include is an instruction, not an actual inclusion.
As opposed to dynamic linking, there is no combined entity being formed
for the sake of execution where one could possibly claim "contributory
infringement".  The inner workings of english.ly and its interoperation
with LilyPond proper are not being accessed or questioned, either.

> (For example, english.ly is explicitly licensed under GPLv3+ without
> any exception.  Yes, I know that these days you should use \language
> "english", but that's beside the point.)

If you convert english.ly into, say, an Elisp file parsing note names,
things are different.

> I can't imagine it's intentional that Lilypond copyleft should extend
> so far as the .ly files of scores created by users, but as things
> stand I'm concerned that this may be the strict letter of the
> licensing.

I don't see that, short of _actual_ inclusion of english.ly etc.

-- 
David Kastrup