Out.t
An output stream, ie. a place into which we can write bytes.
This can be a Buffer.t, an out_channel, a Unix.file_descr, etc. It must be buffered to amortize the cost of individual small writes (including output_char).
Buffer.t
out_channel
Unix.file_descr
output_char
method output_char : char -> unit
Output a single char
method output : bytes -> int -> int -> unit
Output slice
method flush : unit -> unit
Flush underlying buffer
method close : unit -> unit
Close the output. Must be idempotent.