10 exception Io of string
19 val arctan: real -> real
20 val chr: int -> string
21 val close_in: instream -> unit
22 val close_out: outstream -> unit
24 val end_of_stream: instream -> bool
26 val explode: string -> string list
27 val implode: string list -> string
28 val input: instream * int -> string
30 val lookahead: instream -> string
31 val open_in: string -> instream
32 val open_out: string -> outstream
33 val ord: string -> int
34 val output: outstream * string -> unit
36 val sqrt: real -> real
38 val std_out: outstream