Re: problems with learning lilypond

[Simon Mackenzie]

Simon


On 08/08/2009, at 05:41, Trevor Daniels wrote:

> Simon Mackenzie wrote Friday, August 07, 2009 3:55 PM
> > Eg. What does it mean on page 34 of the Learning Tutorial when it
> > says...
> >
> > "Variables must be defined before the main music expression."
> >
> > Does this mean the \score { } or does it mean the expression in which
> > the declared variable is referenced?
>
> The former, as shown quite clearly in the
> template you mention below.

Implied but I feel not so clearly stated. If you declare a \book scope  
which contains \bookpart(s) with \score(s) where are variables to be  
declared? If I understand this all correctly variables must be  
declared outside this/these scope(s)? Correct? (as you have mentioned  
below variables must be declared outside (adding ALL would be helpful  
here) braces.

> > Because I dutifully declare my variables before the \score { } in my
> > script file using the example template from "A.1.4 Notes, lyrics and
> > chords" on page 143, again of the learning manual.
> > End result...
> > This error when I compile my script
> >
> > "Unexpected string"  errors for every variable I've declared and no
> > idea as to why the template example fails to perform as claimed in  
> > the
> > documentation.
> >
> > harmonies = \chordmode {...
> > melody = \lyricmode {... etc. generate "Unexpected string" errors
>
> The template in the manual certainly does compile
> without errors, as the image just below it is the
> direct result of a compilation.  I suggest you
> look at the template on the website at
> http://lilypond.org/doc/v2.12/Documentation/user/lilypond-learning/Single-staff#Single-staff
> From this page you can either copy&paste the code
> directly, or click on the image of the music to
> open the file directly (in the latter case you
> will need to delete the first three lines).  These
> files will then compile correctly (I've just tried
> it).

Agreed, have tested same with complete success which is why I  
mentioned "scoping" in my last post.

> From the error message it looks as if you are
> inserting braces round the whole.  Variable
> definitions come before any braces.
>
> I'll add a bit to the manual to make that clear.

Will definitely help would-be travelers such as myself, thank you.

Here is my scenario

If I create a variable at the top scope how do I reassign its value in  
a subsequent scope eg.

aVariable = \markup { \bold bananas }

\book {
        \bookpart {
                \aVariable % "bananas"
                \score {
			aVariable = \markup { \bold now \italic { equals this string } %  
want to be to reassign aVariable a new value so that...
                        \aVariable % "now equals this string"
                }
        }
}

> Trevor

Thank you for your comments
Simon