Re: Scheme: default values?

[Graham King]

On Sun, 2014-02-02 at 08:51 +0100, Marc Hohl wrote:
> Am 29.01.2014 06:41, schrieb Graham King:
> > To generate MIDI output, I use a piece of boilerplate lilypond code,
> > containing:
> >      \midi { \context { \Score tempoWholesPerMinute = #currentTempo }}
> > where it is expected that:
> >      currentTempo = #(ly:make-moment TACTUS RF)
> >
> > I would like to generalise the boilerplate code so that it works with
> > suitable defaults even when these variables have not been defined.
> 
> Where do you want to define these variables? If you want to use them
> via the command line, you can do it as follows (untested!):
> 

Thanks Marc.  Normally, TACTUS and RF would be defined at the top level
of a .ly file that \include's the boilerplate.  I'm now wondering
whether Guile's catch and throw mechanism is the way to go.  There's
some reading and experimenting ahead...