right and left hyphen

basic_format_and_style_settings.ly

@@ -148,3 +148,14 @@ repStopWithTag = \lyricmode {
     \set stanza = \markup { \repStop }
   }
 }
+
+rightHyphen = \lyricmode {
+  \once \override StanzaNumber.font-series = #'normal
+  \once \override StanzaNumber.direction = 1
+  \set stanza = "-"
+}
+
+leftHyphen = \lyricmode {
+  \once \override StanzaNumber.font-series = #'normal
+  \set stanza = "-"
+}