Transformation of Applicative Specifications into Imperative ...

8.4. SPECIFICATION OF THE TRANSFORMER IN RSL1
vel, et, typings, func, trans, env, types),
NoValueExprPairList →
mk_BOOL_ENV_TYPES(true, env, types)
end
8.4.2 Let Expressions
As let expressions are not a part of RSL1, all let expressions must be removed.
This is done by inserting the actual value of the bindings in the
value expression. In cases where the let bindings are products, the destructors
of the short record definitions which were introduced in Section 8.4.1,
are exploited in order to obtain the desired values. An example of such a
change can be found in Example 8.3.
Example 8.3 – Removing let expressions
RSL specification:
value
TROptPreCondition :
OptionalPreCondition × ExpType × FUNC × TRANS ×
TYPES →
OptionalPreCondition × TYPES
TROptPreCondition(precond, et, func, trans, types) ≡
case precond of
PreCondition(ve) →
let
(ve ′ , types ′ ) =
TRValueExpr(ve, et, func, trans, types)
in
(PreCondition(ve ′ ), types ′ )
end,
NoPreCondition → (NoPreCondition, types)
end
RSL1 specification:
type
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