DEFINITION MODULE STextIO;

(* Input and output of character and string types over default channels.
   The read result is of the type IOConsts.ReadResults.
*)

(* The following procedures do not read past line marks: *)

PROCEDURE ReadChar (VAR ch : CHAR);
(* If possible, removes a character from the input stream and assigns
   the corresponding value to the parameter ch.
   The read result is set to allRight, endOfLine or endOfInput. *)

PROCEDURE ReadRestLine (VAR s : ARRAY OF CHAR);
(* Removes any remaining characters before the next line mark copying
   as many as can be accommodated to the parameter s as a string value.
   The read result is set to the value allRight, outOfRange, endOfline,
   or endOfInput. *)

PROCEDURE ReadString (VAR s : ARRAY OF CHAR);
(* Removes and copies only those characters before the next line mark
   that can be accommodated to the parameter s as a string value.
   The read result is set to the value allRight, endOfLine, or endOfInput. *)

PROCEDURE ReadToken (VAR s : ARRAY OF CHAR);
(* Skips leading spaces and then removes characters before the next
   space or line mark copying as many as can be accommodated to the
   parameter s as a string value.
   The read result is set to the value allRight, outOfRange, endOfLine,
   or endOfInput. *)

(* The following procedure reads past the next line mark *)

PROCEDURE SkipLine;
(* Removes successive items from the input stream up to and including
   the next line mark or until the end of input is reached.
   The read result is set to the value allRight or endOfInput. *)

(* Output procedures *)

PROCEDURE WriteChar (ch : CHAR);
(* Writes the parameter ch to the output stream *)

PROCEDURE WriteLn;
(* Writes a line mark to the output stream *)

PROCEDURE WriteString (s : ARRAY OF CHAR);
(* Writes the string value of the parameter s to the output stream *)

END STextIO.
