Re: Accessing header information for use in a Scheme script

[Rafael Ramirez Morales]

YES. Exactly like that! Thank you.

That solves point 1/ & 2/, and with some minor tweaks, I can hack a solution for point 3.

%% BEGIN workcase

#(define header-alist

  (let* ((defaultheader-entries (ly:module->alist $defaultheader))

         (defaults

           '("title-default"

             "instrument-default"

             "tagline-default"

             "Copyright unknown"

             ;; to be continued

             ))

;; if you want a subset use below

;; otherwise probably (map car defaultheader-entries)

         (entries

           '(title

             instrument

             tagline

             copyright

             ;; to be continued

             )))

  (map

    (lambda (e d)

      (cons (symbol->string e)

        (if (assoc-get e defaultheader-entries)

            (markup->string (assoc-get e defaultheader-entries))

            d)))

    entries

    defaults)))

#(define use-alist '(

                      ( "Public Domain" . "Free to duplicate, distribute, modify, and perform." ) 

                      ( "Copyright" . "All rights reserved." )

                      )

   )

#(define copyright (assoc-get "copyright" header-alist))

#(if (assoc copyright use-alist)

     (define copyrightUse

       (cdr (assoc copyright use-alist))

       )

     (define copyrightUse "Copyright status not defined. Some or all rights might be reserved.")

     )

\header {

  title="My own title" % Comment out to see the magic ;)

  copyright = "Public Domain" % Comment out or change to "Copyright" to see the magic ;)

}

\markup \with-color #red #(assoc-get "title" header-alist)

\markup \with-color #red #(assoc-get "copyright" header-alist)

\markup \with-color #red #copyrightUse

\header {

  title = #(assoc-get "title" header-alist)

  copyright = #(markup (#:concat (copyright "—" copyrightUse)))

}

%% END workcase

GREAT! It works!

A couple of follow-up questions:

Is there a cleaner approach to my second hack (for the copyright notice)?

Is there a Scheme way to set the header variables?

Oh, and one last thing...

Is this code you wrote snippet worthy? 

I obviously find it most useful, but I'm personally convinced it could be of interest to others as well.

On 17 February 2016 at 12:19, Thomas Morley <address@hidden> wrote:

#(define license-alist
  (let* ((defaultheader-entries (ly:module->alist $defaultheader))
         (defaults
           '("title-default"
             "instrument-default"
             "tagline-default"
             "copyright-default"
             ;; to be continued
             ))
;; if you want a subset use below
;; otherwise probably (map car defaultheader-entries)
         (entries
           '(title
             instrument
             tagline
             copyright
             ;; to be continued
             )))
  (map
    (lambda (e d)
      (cons (symbol->string e)
        (if (assoc-get e defaultheader-entries)
            (markup->string (assoc-get e defaultheader-entries))
            d)))
    entries
    defaults)))

%#(display-scheme-music license-alist)

\markup \with-color #red #(assoc-get "title" license-alist)

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