Bool = {true, false}
not: Bool -> Bool
not(false) = true; not(true) = false
equalbool: Bool × Bool -> Bool
equalbool(m, n) = (m=n)
Int = {..., -1, 0, 1, ...}
plus: Int x Int ->
Int
plus(m, n) = m+n
equalint: Int x Int ->
Bool
equalint(m, n) = (m=n)
Location = {loc_i | i>0}