+class Buffer;
+
+/* Toc types are described by strings. They cannot be converted into an enum
+ * because of the user-configurable categories for index and the user-definable
+ * toc types provided in layout files.
+ *
+ * Here is a summary of built-in toc types
+ *
+ * Non-customizable (used without TocBuilder): "tableofcontents", "change",
+ * "citation", "label", "senseless".
+ *
+ * Built-in but customizable (used with TocBuilder): "child", "graphics",
+ * "equation", "index", "index:<user-str>", "nomencl", "listings", "math-macro",
+ * "external", any float type (as defined in the layouts).
+ *
+ * The following are used for XHTML output: "tableofcontents" (InsetText),
+ * "citation" (InsetCitation), any float type.
+ *
+ * Other types are defined in the layouts.
+ */
+