DEFINITION MODULE LowReal;

  (* Access to underlying properties of the type REAL *)

CONST
  radix =      2;
  places =     32;
  expoMin =    -126;
  expoMax =    127;
  large =      3.402823E+38;
  small =      1.175494E-38;
  IEEE =       TRUE;
  ISO =        FALSE;
  rounds =     TRUE;
  gUnderflow = FALSE;
  exception =  TRUE;
  extend =     TRUE;
  nModes =     6;

TYPE
  Modes = SET OF [0 .. nModes-1];

PROCEDURE exponent (x: REAL): INTEGER;
  (* Returns the exponent value of x *)

PROCEDURE fraction (x: REAL): REAL;
  (* Returns the significand (or significant part) of x *)

PROCEDURE sign (x: REAL): REAL;
  (* Returns the signum of x *)

PROCEDURE succ (x: REAL): REAL;
  (* Returns the next value of the type REAL greater than x *)

PROCEDURE ulp (x: REAL): REAL;
  (* Returns the value of a unit in the last place of x *)

PROCEDURE pred (x: REAL): REAL;
  (* Returns the previous value of the type REAL less than x *)

PROCEDURE intpart (x: REAL): REAL;
  (* Returns the integer part of x *)

PROCEDURE fractpart (x: REAL): REAL;
  (* Returns the fractional part of x *)

PROCEDURE scale (x: REAL; n: INTEGER): REAL;
  (* Returns the value of x * radix ** n *)

PROCEDURE trunc (x: REAL; n: INTEGER): REAL;
  (* Returns the value of the first n places of x *)

PROCEDURE round (x: REAL; n: INTEGER): REAL;
  (* Returns the value of x rounded to the first n places *)

PROCEDURE synthesize (expart: INTEGER; frapart: REAL): REAL;
  (* Returns a value of the type REAL constructed from the given expart and frapart *)

PROCEDURE setMode (m: Modes);
  (* Sets status flags appropriate to the underlying implementation of the type REAL *)

PROCEDURE currentMode (): Modes;
  (* Returns the current status flags in the form set by setMode *)

PROCEDURE IsLowException (): BOOLEAN;
  (* Returns TRUE if the current coroutine is in the exceptional execution state
     because of the raising of an exception in a routine from this module; otherwise
     returns FALSE.
  *)

END LowReal.

