Fix 380: Try to auto-detect cyclic references in header fields

[lilypond.git] / scm / define-markup-commands.scm

diff --git a/scm/define-markup-commands.scm b/scm/define-markup-commands.scm
index 18728e57d9809de9b1865209cfb5e7677103b59d..803b691215cf864950838d7280fecb1731968c7b 100644 (file)
--- a/scm/define-markup-commands.scm
+++ b/scm/define-markup-commands.scm
@@ -937,25 +937,45 @@ the use of @code{\\simple} is unnecessary.
 Like simple-markup, but use tie characters for @q{~} tilde symbols.
 
 @lilypond[verbatim,quote]
-\\markup {
-  \\tied-lyric #\"Lasciate~i monti\"
-}
-@end lilypond"
-  (if (string-contains str "~")
-      (let*
-         ((half-space (/ word-space 2))
-          (parts (string-split str #\~))
-          (tie-str (markup #:hspace half-space
-                           #:musicglyph "ties.lyric"
-                           #:hspace half-space))
-          (joined  (list-join parts tie-str))
-          (join-stencil (interpret-markup layout props tie-str))
-          )
+\\markup \\column {
+  \\tied-lyric #\"Siam navi~all'onde~algenti Lasciate~in abbandono\"
+  \\tied-lyric #\"Impetuosi venti I nostri~affetti sono\"
+  \\tied-lyric #\"Ogni diletto~e scoglio Tutta la vita~e~un mar.\"
+}
+@end lilypond"
+  (define (replace-ties tie str)
+    (if (string-contains str "~")
+        (let*
+          ((half-space (/ word-space 2))
+           (parts (string-split str #\~))
+           (tie-str (markup #:hspace half-space
+                            #:musicglyph tie
+                            #:hspace half-space))
+           (joined  (list-join parts tie-str)))
+          (make-concat-markup joined))
+        str))
+
+  (define short-tie-regexp (make-regexp "~[^.]~"))
+  (define (match-short str) (regexp-exec short-tie-regexp str))
+
+  (define (replace-short str mkp)
+    (let ((match (match-short str)))
+      (if (not match)
+          (make-concat-markup (list
+            mkp
+            (replace-ties "ties.lyric.default" str)))
+          (let ((new-str (match:suffix match))
+                (new-mkp (make-concat-markup (list
+                          mkp
+                          (replace-ties "ties.lyric.default"
+                                        (match:prefix match))
+                          (replace-ties "ties.lyric.short"
+                                        (match:substring match))))))
+              (replace-short new-str new-mkp)))))
 
-       (interpret-markup layout
-                         props
-                         (make-concat-markup joined)))
-      (interpret-markup layout props str)))
+  (interpret-markup layout
+                    props
+                    (replace-short str (markup))))
 
 (define-public empty-markup
   (make-simple-markup ""))
@@ -1863,6 +1883,14 @@ Add padding @var{amount} around @var{arg} in the X@tie{}direction.
 ;; property
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+(define-markup-command (property-recursive layout props symbol)
+  (symbol?)
+  #:category other
+  "Print out a warning when a header field markup contains some recursive
+markup definition."
+  (ly:warning "Recursive definition of property ~a detected!" symbol)
+  empty-stencil)
+
 (define-markup-command (fromproperty layout props symbol)
   (symbol?)
   #:category other
@@ -1885,7 +1913,8 @@ returns an empty markup.
 @end lilypond"
   (let ((m (chain-assoc-get symbol props)))
     (if (markup? m)
-        (interpret-markup layout props m)
+        ;; prevent infinite loops by clearing the interpreted property:
+        (interpret-markup layout (cons (list (cons symbol `(,property-recursive-markup ,symbol))) props) m)
         empty-stencil)))
 
 (define-markup-command (on-the-fly layout props procedure arg)