Transformation of Applicative Specifications into Imperative ...

6.4. TRANSFORMING EXPLICIT FUNCTION DEFINITIONS
The type of value_expr:
1. does not contain T.
Transformation: The letbinding is transformed into itself, see function
f1 in Example 6.11.
2. is T.
Transformation: A so called "dummy" binding is inserted in order to
keep the let expression and the order of the let definitions, see function
f2 in Example 6.11.
3. is a product in which T occurs.
Transformation: The bindings corresponding to the values of the
type of interest are removed from the letbinding, see function f3 in
Example 6.11
Example 6.11 – Transformation of let expressions
scheme A_SPEC =
class
type
T = Int
end
value
f1 : T → Int
f1(x) ≡ let z = obs(x) in z end,
f2 : Int → Int
f2(x) ≡ let x1 = gen1(x) in x1 + 1 end,
f3 : Int → Int
f3(x) ≡ let (x1, z) = gen2(x) in z end,
obs : T → Int
obs(x) ≡ x,
gen1 : Int → T
gen1(x) ≡ x + 1,
gen2 : Int → T × Int
gen2(x) ≡ (x + 1, x − 1)
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