Structure SML90

(* Old -- compatibility with the initial basis of the 1990 Definition *)

(* Math *)

val sqrt : real -> real
val sin : real -> real
val cos : real -> real
val arctan : real -> real
val exp : real -> real
val ln  : real -> real

(* Strings *)

val chr : int -> string
val ord : string -> int

val explode : string -> string list
val implode : string list -> string

exception Abs  
      and Diff 
      and Exp  
      and Floor
      and Neg  
      and Prod 
      and Sum  
      and Mod  
      and Quot;

(* Input/output *)

type instream and outstream;

val std_in        : instream;
val open_in       : string -> instream;
val input         : instream * int -> string;
val lookahead     : instream -> string;
val close_in      : instream -> unit;
val end_of_stream : instream -> bool;

val std_out       : outstream;
val open_out      : string -> outstream;
val output        : outstream * string -> unit;
val close_out     : outstream -> unit;