(* Library module defined by the International Standard
   Information technology - programming languages
   BS ISO/IEC 10514-1:1996E Part 1: Modula-2, Base Language.

   Copyright ISO/IEC (International Organization for Standardization
   and International Electrotechnical Commission) 1996-2021.

   It may be freely copied for the purpose of implementation (see page
   707 of the Information technology - Programming languages Part 1:
   Modula-2, Base Language.  BS ISO/IEC 10514-1:1996).  *)

DEFINITION MODULE SRealIO;

  (* Input and output of real numbers in decimal text form over
     default channels.  The read result is of the type
     IOConsts.ReadResults.
  *)

  (* The text form of a signed fixed-point real number is
       ["+" | "-"], decimal digit, {decimal digit},
       [".", {decimal digit}]

     The text form of a signed floating-point real number is
       signed fixed-point real number,
       "E", ["+" | "-"], decimal digit, {decimal digit}
  *)

PROCEDURE ReadReal (VAR real: REAL);
  (* Skips leading spaces, and removes any remaining characters
     from the default input channel that form part of a signed
     fixed or floating point number. The value of this number
     is assigned to real.  The read result is set to the value
     allRight, outOfRange, wrongFormat, endOfLine, or endOfInput.
  *)

PROCEDURE WriteFloat (real: REAL; sigFigs: CARDINAL; width: CARDINAL);
  (* Writes the value of real to the default output channel in
     floating-point text form, with sigFigs significant figures,
     in a field of the given minimum width.
  *)

PROCEDURE WriteEng (real: REAL; sigFigs: CARDINAL; width: CARDINAL);
  (* As for WriteFloat, except that the number is scaled with one to
     three digits in the whole number part, and with an exponent that
     is a multiple of three.
  *)

PROCEDURE WriteFixed (real: REAL; place: INTEGER; width: CARDINAL);
  (* Writes the value of real to the default output channel in
     fixed-point text form, rounded to the given place relative
     to the decimal point, in a field of the given minimum width.
  *)

PROCEDURE WriteReal (real: REAL; width: CARDINAL);
  (* Writes the value of real to the default output channel, as
     WriteFixed if the sign and magnitude can be shown in the
     given width, or otherwise as WriteFloat. The number of
     places or significant digits depends on the given width.
  *)

END SRealIO.

