module Buf:Character buffers. Similar to Buffer.sig..end
type buf
val create : int -> bufcreate n creates the buffer. n is used to determine
the initial size of the buffer. The meaning of n differs from
modules to modules.val contents : buf -> UnicodeString.Type.tval clear : buf -> unitval reset : buf -> unitval add_char : buf -> UChar.t -> unitval add_string : buf -> UnicodeString.Type.t -> unitval add_buffer : buf -> buf -> unit