Transformation of Applicative Specifications into Imperative ...

Chapter 10
Examples of Transformations
In order to give an idea of how the transformer works a couple of examples
of transformations are given in this chapter. The first example just shows
an example of applying the transformer to an applicative specification. The
second example shows the development process from initial specification to
imperative specification emphasizing the use of the transformer in the development
process.
10.1 The Stack
The stack example given in Chapter 2 is transformed by hand. In order to
show that the automatic transformation done by the transformer follows the
principles given in that chapter, the stack specification has been transformed
using the transformer. The result can be seen in Example 10.1. For easy
reference the applicative version of the stack specification is repeated here.
Example 10.1 – Automatic transformation of the stack example
scheme A_STACK =
class
type
Stack = Element ∗ ,
Element
value
empty : Stack = 〈〉,
is_empty : Stack → Bool
is_empty(stack) ≡ stack = 〈〉,
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