use new lilypond 2.25 regexes and font definitions

legacy-lilypond-compatibility-pre-2.25.ly

@@ -0,0 +1,22 @@
+% guile regular expressions aktivieren:
+#(use-modules (ice-9 regex))
+
+#(define ly:make-regex make-regexp)
+#(define ly:regex-exec regexp-exec)
+#(define ly:regex-match-substring match:substring)
+#(define (ly:regex-replace pattern text . replacements)
+  (apply regexp-substitute/global #f pattern text 'pre (append replacements (list 'post))))
+
+
+% old font handling
+
+#(define (default-pango size)
+  (make-pango-font-tree
+    songChordFont
+    songLyricFont
+    "Luxi Mono"
+    (/ size 20)))
+
+\paper {
+  #(define fonts (default-pango globalSize))
+}