Counter

Z

  • Counter \defs [ n : \nat  |  n ≥ 0 ]

  • Counter::Incr \defs [ ∆Counter, v? : \nat  |  n′ = n + v? ]

  • Counter::Decr \defs [ ∆Counter  |  n > 0; n′ = n − 1 ]

  • Counter::Value \defs [ ΞCounter; v! : \nat  |  v! = n ]

Bounded counter

  • Counter \defs [ n : \nat  |  n ≥ 0 ]

  • Counter::Incr \defs [ ∆Counter, v? : \nat  |  n′ = n + v? ]

  • Counter::Decr \defs [ ∆Counter  |  n > 0; n′ = n − 1 ]

  • Counter::Value \defs [ ΞCounter; v! : \nat  |  v! = n ]


slide: An alternative specification of the Counter