One early comment :-)
https://codereview.appspot.com/547340043/diff/575390044/lily/break-alignment-interface.cc File lily/break-alignment-interface.cc (right): https://codereview.appspot.com/547340043/diff/575390044/lily/break-alignment-interface.cc#newcode328 lily/break-alignment-interface.cc:328: Break_alignable_interface::self_alignment_cis_breakable (SCM grob) Well, the cis–trans pairing is IMHO only understandable for people who have a Latin background (or come from Austria, since it was divided into »Cisleithanien« and »Transleithanien« in the K. und K. era)... As nice as it is, I suggest that you find names that are easier to comprehend for other people. https://codereview.appspot.com/547340043/
