Re: LilyPond, LilyPond snippets and the GPL

[Hans Åberg]

> On 31 Oct 2019, at 03:15, Carl Sorensen <address@hidden> wrote:
> 
>> On 10/30/19, 5:13 PM, "Hans Åberg" <address@hidden> wrote:
>> 
>>> On 30 Oct 2019, at 22:14, Carl Sorensen <address@hidden> wrote:
>>> 
>>>   The snippets should be LGPL for being includable under other licenses, I 
>>> believe, because the processed part remains in the output, and thus 
>>> copyrightable. Thus, they play the same role as the Bison skeleton file and 
>>> GCC libraries.
>>> 
>>> What processed part remains in the output?
>> 
>>    If say somebody makes a snippet on how to make special type of clef, then 
>> that is copyrightable, just as a font and its glyphs are, it would seem, and 
>> that copyright will remain if copy-and-pasted into user code.
> 
> In the US, a typeface is not copyrightable.  But a computer program that 
> makes a font or its glyphs is copyrightable.  I can see your argument here.  
> But if this argument is true, then it seems that all music set with LilyPond 
> is GPL3,  because the code for drawing beams, stems, staff lines, and 
> straight flags is in LilyPond and is licensed under GPL3.  I find it very 
> hard to believe that this is true.  And certainly, as far as the FSF is 
> concerned, this is not true.  

All those parts should be LGPL, and also included headers, I believe: Not GPL, 
because that would legal technically force copyright limitations on the output, 
and not public domain, because then one could exploit the inputs in ways you do 
not want. But check with the experts.