Instanciable scheme engravers

[lilypond.git] / lily / translator-group.cc

diff --git a/lily/translator-group.cc b/lily/translator-group.cc
index 44b4e1fe0a1742dbb1e2fb34eeada2589004c2cd..dc2b772428f681e935d6e089f7fbffe16610bb87 100644 (file)
--- a/lily/translator-group.cc
+++ b/lily/translator-group.cc
@@ -167,6 +167,16 @@ Translator_group::create_child_translator (SCM sev)
          instance = type->clone ();
          dynamic_cast<Scheme_engraver*> (instance)->init_from_scheme (definition);
        }
+      else if (ly_is_procedure (definition))
+       {
+         // `definition' is a procedure, which takes the context as
+         // an argument and evaluates to an a-list scheme engraver
+         // definition.
+         SCM def = scm_call_1 (definition, cs);
+         type = get_translator (ly_symbol2scm ("Scheme_engraver"));
+         instance = type->clone ();
+         dynamic_cast<Scheme_engraver*> (instance)->init_from_scheme (def);
+       }
         
       if (!type)
        warning (_f ("cannot find: `%s'", ly_symbol2string (scm_car (s)).c_str ()));