Re: guileV2 and Lilypond (was: Strings as variable names)

[Paul Morris]

> On Jan 3, 2016, at 11:14 AM, Menu Jacques <address@hidden> wrote:
> 
> A newbie question: what are the expected benefits and challenges of moving 
> from guile 1.8.x to guile 2.y?

As I understand it, guile 2.0 introduced significant performance improvements, 
mainly for compiled scheme, but since LilyPond interprets scheme, and the 
scheme interpreter in guile 2.0 is actually slower than in 1.8 (but faster in 
2.2 than in 2.0)  …just how much of the performance benefits LilyPond will 
enjoy remains to be seen.

One of the immediate benefits is just keeping up with the current guile version 
distributed with gnu/linux distributions.  They don’t want to keep including 
guile 1.8 just for LilyPond’s sake, so LilyPond could get dropped from these 
distributions.

But the big story is the challenges -- mainly that guile 2.0 still has bugs 
that need to be fixed for it to work reliably with LilyPond.

I recently saw this announcement about guile 2.1.1 the "first pre-release in 
what will become the 2.2 stable series”:
http://savannah.gnu.org/forum/forum.php?forum_id=8397

That led me to the redesigned guile website and their mailing list, where I 
found a post that touches on the need for better LilyPond support in guile:
http://lists.gnu.org/archive/html/guile-devel/2015-11/msg00005.html

And this follow-up post that clearly lays out the current showstopper bug: 
http://lists.gnu.org/archive/html/guile-devel/2015-11/msg00031.html

Maybe that sheds some light on this.  Clarifications and additions welcome.

-Paul