*
* A concrete ligature engraver must subclass this class and provide
* functions create_ligature_spanner () and typeset_ligature
- * (Spanner *, std::vector<Grob_info>). Subclasses of this class basically
+ * (Spanner *, vector<Grob_info>). Subclasses of this class basically
* fall into two categories.
*
* The first category consists of engravers that engrave ligatures in