(* Version 1.10, Nov 1984 *)
DEFINITION MODULE CardinalIO;
(*
   Terminal input/output of CARDINALs in decimal and hex

Derived from the Lilith Modula-2 system developed by the
group of Prof. N. Wirth at ETH Zurich, Switzerland.
*)

EXPORT QUALIFIED
   ReadCardinal, WriteCardinal, ReadHex, WriteHex;


PROCEDURE ReadCardinal (VAR c: CARDINAL);
(*
- Read an unsigned decimal number from the terminal.
out:    c       the value that was read.

The read terminates only on ESC, EOL, or blank, and the
terminator must be re-read, for example with Terminal.Read.

If the read encounters a non-digit, or a digit which would
cause the number to exceed the maximum CARDINAL value, the
bell is sounded and that character is ignored.  No more
than one leading '0' is allowed.
*)

PROCEDURE WriteCardinal (c: CARDINAL; w: CARDINAL);
(*
- Write a CARDINAL in decimal format to the terminal.
in:     c       value to write,
        w       minimum field width.

The value of c is written, even if it takes more than w
digits. If it takes fewer digits, leading blanks are
output to make the field w characters wide.
*)

PROCEDURE ReadHex (VAR c: CARDINAL);
(*
- Read a CARDINAL in hexadecimal format from the terminal.
  [see ReadCardinal above]
*)

PROCEDURE WriteHex (c: CARDINAL; digits: CARDINAL);
(*
- Write a CARDINAL in hexadecimal format to the terminal.
  [see WriteCardinal above]
*)

END CardinalIO.
