---------------------- MODULE clock_init0 ----------------------
EXTENDS Naturals
VARIABLES
hours,
minutes,
seconds
Init == hours = 0
/\ minutes = 0
/\ seconds = 0
Next == hours' = (IF minutes # 59 THEN hours ELSE (hours + 1) % 12)
/\ minutes' = (IF seconds # 59 THEN minutes ELSE (minutes + 1) % 60)
/\ seconds' = (seconds + 1) % 60
Clock == Init /\ [][Next]_<<hours, minutes, seconds>>
--------------------------------------------------------------
THEOREM Clock => []Init
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