#include FSET.cam

; Creation date: Thu Dec 11 19:12:57 WET 1997

STATE st: (A-set)-set;

FUNC INIT(a: A-set): VOID
STATE  st <- { {x} | x <- a };

FUNC EQU(a: A, b: A): VOID
STATE let (s={ x | x <- st: ~(a in x || b in x) },
           r= st - s)
      in  st <- s U { UNION(r) };

FUNC ETEST(a: A, b: A): BOOL
RETURN the({ s | s <- st: a in s}) == the({ s | s <- st: b in s});

FUNC CLASS(a: A): A-set
RETURN the({ s | s <- st: a in s});