# The RealType interface

An `RealType.T` is a `REAL`. This interface is intended to be used to instantiate generic interfaces and modules such as `Table` and `List`.

    INTERFACE RealType;

    IMPORT Word;

    TYPE T = REAL;

    CONST Brand = "Real";

    PROCEDURE Equal(a, b: T): BOOLEAN;

Return `a = b`. The result is undefined if either `a` or `b` is an `NaN` (not a number) value.

    PROCEDURE Hash(a: T): Word.T;

Return a hash value derived from `a`. The result is undefined if either `a` or `b` is an `NaN` (not a number) value.

    PROCEDURE Compare(a, b: T): [-1..1];

Return `-1` if `a < b", "0" if "a = b", or "+1" if "a > b`. The result is undefined if either `a` or `b` is an `NaN` (not a number) value.

    END RealType.