1 ;;;; This file is part of LilyPond, the GNU music typesetter.
3 ;;;; Copyright (C) 2004--2011 Nicolas Sceaux <nicolas.sceaux@free.fr>
4 ;;;; Jan Nieuwenhuizen <janneke@gnu.org>
6 ;;;; LilyPond is free software: you can redistribute it and/or modify
7 ;;;; it under the terms of the GNU General Public License as published by
8 ;;;; the Free Software Foundation, either version 3 of the License, or
9 ;;;; (at your option) any later version.
11 ;;;; LilyPond is distributed in the hope that it will be useful,
12 ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
13 ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 ;;;; GNU General Public License for more details.
16 ;;;; You should have received a copy of the GNU General Public License
17 ;;;; along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
19 (define-public (read-lily-expression chr port)
20 "Read a lilypond music expression enclosed within @code{#@{} and @code{#@}}
21 from @var{port} and return the corresponding Scheme music expression.
22 @samp{$} and @samp{#} introduce immediate and normal Scheme forms."
23 (let ((lily-string (call-with-output-string
25 (do ((c (read-char port) (read-char port)))
27 (char=? (peek-char port) #\})) ;; we stop when #} is encountered
29 ;; a #scheme or $scheme expression
30 (if (or (char=? c #\#) (char=? c #\$))
31 (format out "~a~s" c (read port))
35 (ly:parser-clone parser (procedure-environment (lambda () '()))))
37 (ly:parser-clear-error clone)
38 (ly:parse-string-expression clone ,lily-string))))
39 (if (ly:parser-has-error? clone)
40 (ly:parser-error parser (_ "error in #{ ... #}")))
43 (read-hash-extend #\{ read-lily-expression)