Transformation of Applicative Specifications into Imperative ...

4.1. THE RSL CONSTRUCTIONS NOT CONSIDERED
• Function expressions.
Reason: To simplify matters. In some cases function expressions can
be rewritten by introducing a new function at outermost level.
• Initialise expressions.
Reason: Initialise expressions are not considered as the initial values
of the established variables are unknown. This means that an initialse
expression would have no effect.
• Infinite map expressions.
Reason: To simplify matters. Due to major revisions needed in one
of the tools used in order to be able to do the transformation of infinite
map expressions, infinite map expressions are left out. Furthermore,
infinite maps are not widely used.
• Test cases.
Reason: To simplify matters.
Non-Syntactical Constraints
• Subtype expressions in which a type of interest is part of the single
typing.
Reasons: The transformation of subtype expressions in which a type
of interest is part of the single typing would lead to a syntactically
wrong imperative specification.
• Explicit value definitions of the form product_binding : type_expr =
value_expr.
Reason: To simplify matters. Furthermore, most value definitions of
the form product_binding : type_expr = value_expr can be rewritten
by establishing more explicit value definitions, one for each id_binding
in the product_binding.
• The type expression of a single typing of an explicit function definition
shall be a function type expression.
Reason: To simplify matters. Furthermore, this can easily be accomplished
by inserting the actual type of the function instead of using a
corresponding type name.
• Higher order functions.
Reason: To simplify matters. In some cases higher order functions
can be rewritten into normal functions, e.g. a function of the type U
→ T → V can be rewritten into a function of the type U × T → V.
• Collections of values of the types of interest such as sets and lists of
values of the types of interest and maps containing values of the types
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