+ /*! \brief
+ * Creates a subsection in the output help.
+ *
+ * \param[in] title Title for the subsection.
+ * \throws std::bad_alloc if out of memory.
+ * \throws FileIOError on any I/O error.
+ *
+ * Writes \p title using writeTitle() and makes any further
+ * writeTitle() calls write headings one level deeper.
+ *
+ * Typical use for writing a subsection is to create a copy of the
+ * context for the parent section, and then call enterSubSection() on
+ * the copy.
+ * The whole subsection should be written out using the returned
+ * context before calling any further methods in the parent context.
+ *
+ * This method is only necessary if the subsection will contain further
+ * subsections. If there is only one level of subsections, it is
+ * possible to use writeTitle() directly.
+ */
+ void enterSubSection(const std::string &title);
+