`sig type buf = Buffer.t val create : int -> CamomileLibrary.UTF8.Buf.buf val contents : CamomileLibrary.UTF8.Buf.buf -> CamomileLibrary.UTF8.t val clear : CamomileLibrary.UTF8.Buf.buf -> unit val reset : CamomileLibrary.UTF8.Buf.buf -> unit val add_char : CamomileLibrary.UTF8.Buf.buf -> CamomileLibrary.UChar.t -> unit val add_string : CamomileLibrary.UTF8.Buf.buf -> CamomileLibrary.UTF8.t -> unit val add_buffer : CamomileLibrary.UTF8.Buf.buf -> CamomileLibrary.UTF8.Buf.buf -> unit end`