c_gtk_text_buffer_register_serialize_format

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
GdkAtom function(GtkTextBuffer* buffer, const(char)* mimeType, GtkTextBufferSerializeFunc funct, void* userData, GDestroyNotify userDataDestroy) c_gtk_text_buffer_register_serialize_format;

Meta