+ "Write the skeleton of a class declaration.
+
+ Most of the work is done by other functions.
+
+ * The class type is defined by `emit-class-typedef'.
+
+ * The class object is declared by `emit-class-object-decl'.
+
+ * The upcast conversion macros are defined by `emit-class-conversion-
+ macro'.
+
+ * The message invocation macros are defined by `emit-message-macro'.
+
+ * The class instance structure itself is constructed by the `ilayout'
+ object.
+
+ * The various vtable structures are constructed by the `vtable'
+ objects."