Transformation of Applicative Specifications into Imperative ...

CHAPTER 8. SPECIFICATIONS
PRECOND_TYPES ::
preCond : OptionalPreCondition typesMap : TYPES
value
TROptPreCondition :
OptionalPreCondition × ExpType × FUNC × TRANS ×
TYPES →
PRECOND_TYPES
TROptPreCondition(precond, et, func, trans, types) ≡
case precond of
PreCondition(ve) →
mk_PRECOND_TYPES(
PreCondition(
valueExpr(
TRValueExpr(ve, et, func, trans, types))
),
typesMap(
TRValueExpr(ve, et, func, trans, types))),
NoPreCondition →
mk_PRECOND_TYPES(NoPreCondition, types)
end
8.4.3 Lack of Operators
Only a small subset of operators are included in the RSL1 subset. The lack
of these operators makes it necessary to implement their functionality using
functions. Some of the operators are straight forward to implement, whereas
some limit the functionality of the transformer.
An example of the first kind is the inequality operator = and the negation
operator ∼. A solution to the lack of the these operators can be seen in
Example 8.4.
Example 8.4 – Lack of operators – inequality and negation
RSL specification:
.
if tel = 〈〉
then
(false, mk_FormalFunctionParameter(〈〉), env,
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