Transformation of Applicative Specifications into Imperative ...

6.4. TRANSFORMING EXPLICIT FUNCTION DEFINITIONS
Example 6.7 – Transformation of a simple product expression
scheme A_SPEC =
class
type
T = Int
✄
end
value
f : T → Int × Bool × Bool
f(x) ≡ (1 + x − 5, ∼false, obs(x)),
obs : T → Bool
obs(x) ≡ x > 10
scheme I_SPEC =
class
type
T = Int
end
variable
t : T
value
f : Unit → read t write t Int × Bool × Bool
f() ≡ (1 + t − 5, ∼ false, obs()),
obs : Unit → read t Bool
obs() ≡ t > 10
There is one exception to this rule. If the product expression contains
components which have expected type T, it is necessary to establish let
expressions, for example:
(1, gen(2), 3)
✄
let (pa_0, pa_1, pa_2) = (1, gen(2), 3) in (pa_0, pa_2) end
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