Use fractions rather than Scheme pairs for \scaleDuration, timeSignatureFraction et al

Documentation/snippets/new/changing-time-signatures-inside-a-polymetric-section-using--scaledurations.ly

+\version "2.15.17"
+
+\header {
+  lsrtags = "workaround, contexts-and-engravers, contemporary-notation, rhythms"
+
+  doctitle = "Changing time signatures inside a polymetric section using \\scaleDurations"
+}
+
+
+\layout {
+  \context {
+    \Score
+    \remove "Timing_translator"
+    \remove "Default_bar_line_engraver"
+  }
+  \context {
+    \Staff
+    \consists "Timing_translator"
+    \consists "Default_bar_line_engraver"
+  }
+}
+
+<<
+  \new Staff {
+    \scaleDurations 8/5 {

[Keith, 2012/05/13 02:43:23]

Somehow, this worked before the patch.  Not a problem, just an observation.

[dak, 2012/05/13 05:57:27]

Yup.  As I said: 2.15.17 for function arguments (that's when \times 2/3 ...
became a regular function instead of a reserved word in the parser).

+      \time 6/8
+      \set Timing.measureLength = #(ly:make-moment 6 5)
+      b8 b b b b b
+      \time 2/4
+      \set Timing.measureLength = #(ly:make-moment 4 5)
+      b4 b
+    }
+  }
+  \new Staff {
+    \clef bass
+    \time 2/4
+    c2 d e f
+  }
+>>