Transformation of Applicative Specifications into Imperative ...

CHAPTER 6. TRANSFORMATIONS
type
T = Int
variable
t : T
value
obsgen : Unit → read t write t Unit
obsgen() ≡ t := t + 1
Transformation of the Different Value Expressions
In the following the transformations of the different value expressions of
RSLA are given.
Value Literals
The transformation of value literals is straight forward as they have to be
transformed within the same language, namely RSL. This means that a value
literal is transformed into itself.
Value Names
A value name, i.e. either the id of a value declaration, the id of a let binding or
a formal parameter of a function definition, is transformed into itself except
when it is of the type of interest. In that case it is either transformed into
the variable name of the type of interest or, if it is a constant of the type of
interest, it is transformed as an application expression taking no parameters.
Basic Expressions
When dealing with basic expressions it is only necessary to deal with chaos
as the other basic expressions not are part of RSLA. chaos is transformed
into itself.
Product Expressions
A product expression has the following form:
(value_expr1, value_expr2, ..., value_exprn)
A product expression is transformed by transforming the constituent
value expressions one by one, as in Example 6.7.
38