Re: Event listener to extract (some) music events. (issue4373046)

[percival . music . ca]

On 2011/04/18 14:09:52, hanwenn wrote:
> On Mon, Apr 18, 2011 at 4:49 AM,  <mailto:address@hidden>
wrote:
> >

> I cant see any changes. Did you upload?

I think so... when I click on "diff from patchset 4", I see the changes
I made 6 hours ago.

> > Of course different researchers may want to examine different
aspects of
> > the output; the documentation will address that, and once they've
> > modified event-listener.ly to their liking, they might send patches
back
> > to us. &nbsp;The important thing IMO is to have the basic framework
there, so
> > that researchers know that it's possible (and ideally how to get
> > started).

> FWIW, it looks as if you're mostly interested in this at the
> musical-semantic level.

Yes.

> In that case, it would probably be cleaner to
> hook into the event listener framework directly, without having an
> engraver in between.  The Scheme engraver mechanism is really for
> creating formatted output rather than siphoning off data.

I have no clue how to do this?  Is this simple to do with a .ly file?  I
definitely don't want to mess with C++ code or SCM files.

Quite apart from my ignorance of those areas, I want to let this serve
as an example for other people interested in extracting info from
lilypond.  It's much easier to work on a .ly file which you just
\include in your main file, rather than modifying scm files in the
lilypond share dir, or changing C++ code and then recompiling.


> > I like small, focused patches. &nbsp;Documentation comes after the
code is
> > pushed.

> it's hard to do a sensible code review if I can't see what the code is
> meant for.

Well, the easiest way to see what it's for is just to run the regtest
right now; it will spam messages like

0.000   note     57       4   p-c 2 12
0.000   dynamic  f
0.250   note     62       4   p-c 7 12
0.500   note     66       8   p-c 9 12
0.625   note     69       8   p-c 14 12
0.750   rest     0        4

to the console.  That info can be easily read into python using
open("foo.notes").readline(); line.split(), and then you can do whatever
you want with it.


But ok, I'll write the docs now.


http://codereview.appspot.com/4373046/