ly/spanners.ly

   1
   2
   3 % 1st arg dynamic (louder/softer). 2nd arg spantype
   4 cr = \spanrequest \start "crescendo"
   5 decr = \spanrequest  \start "decrescendo"
   6 rc = \spanrequest   \stop "crescendo"
   7 rced = \spanrequest \stop "decrescendo"