Re: book-predicate

[David Kastrup]

Jan-Peter Voigt <address@hidden> writes:

> On 02.03.2012 10:30, David Kastrup wrote:
>> Jan-Peter Voigt<address@hidden>  writes:
>>
>>> Hello David, hello lists,
>>>
>>> now, when we have a book-predicate, we are dealing with books in
>>> scheme. And then we might want to set a header after creating a book.
>>> There is a function ly:score-set-header!, which I copied and adapted
>>> for the Book-class.
>>> This patch compiled and works with the following snippet.
>>>
>>> --snip--
>>> \version "2.15.32"
>>>
>>> bk = \book {
>>>    \score {
>>>      \relative c' {
>>>        c4 e g b
>>>      }
>>>    }
>>> }
>>>
>>> #(let ((bh (eval-string "(define-module (a b))")))
>>>       (eval '(define title "Hallo") bh)
>>>       (ly:book-set-header! bk bh))
>> "eval-string" is not exactly what I call "in Scheme".
>>
>>> \book { \bk }
>>> --snip--
>>>
>>> Is this helpful for lily-devel?
>>> And is there another (better) way of creating a module (for header
>>> generation) on the fly in scheme?
>> make-module would be obvious.
> But if you try a (eval '(define title "Titel") (make-module)) it fails
> with "Unbound variable: define"?

Well, where would a definition for "define" come from in an empty
module?

-- 
David Kastrup