Re: [Lilypond-auto] Issue 2872 in lilypond: Patch: Provide define-session and define-session-public commands

[lilypond]

Comment #17 on issue 2872 by address@hidden: Patch: Provide define-session and  
define-session-public commands
http://code.google.com/p/lilypond/issues/detail?id=2872

After staging had to be rebased, the commit has been changed to
commit 9eb1eba8423cdd66f7bb0e51cb1b6104fe4e3019
Author: David Kastrup <address@hidden>
Date:   Mon Oct 1 14:15:17 2012 +0200

    Issue 2872: Provide define-session and define-session-public commands

    Also moves the session logic into lily.scm instead of init.ly

    A session corresponds to one .ly file on the LilyPond command line;
    sessions are supposed to be processed independently in one LilyPond
    run.

    define-session will declare a variable that has its value recorded at
    the start of the first session and reinstated at the start of each
    following sessions.  This is automatically the case for every variable
    defined in variables in the parser module established while loading
    ly/declarations-init.ly.  However, not every changeable information
    handled in the .scm parts of LilyPond can easily or reasonably be
    stored in the parser module.  define-session (and
    define-session-public) provide a way to get the same semantics for
    variables defined in the Scheme parts of LilyPond.