Transformation of Applicative Specifications into Imperative ...

10.3. USING THE TRANSFORMER
named database. The transformation is done using the following command:
java translator.RSLRunner A_DATABASE3 I_DATABASE1 database:Database
The result can be found in Specification 10.4.
Specification 10.4 – Concrete imperative specification of the database
scheme I_DATABASE1 =
class
type
Database = Key →m Data,
Key,
Data
end
Validation
variable
database : Database
value
empty : Unit → write database Unit
empty() ≡ database := [ ],
insert :
Key × Data → read database write database Unit
insert(k, d) ≡ database := database † [ k ↦→ d ],
remove : Key → read database write database Unit
remove(k) ≡ database := database \ {k},
defined : Key → read database Bool
defined(k) ≡ k ∈ dom database,
lookup : Key ∼ → read database Data
lookup(k) ≡ database(k)
Normally the development step from applicative into imperative specification
cannot be formally verified, but by using the transformation rules, which are
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