Transformation of Applicative Specifications into Imperative ...

C.1. FORMAL SPECIFICATION OF THE TRANSFORMER
Int: the number of type expressions
∗/
getLengthTEL : TypeExpr ∗ → Int
getLengthTEL(tel) ≡
if tel = 〈〉 then 0
else getLengthTE(hd tel) + getLengthTEL(tl tel)
end,
/∗Removes superfluous occurrences of UNIT from
a type expression.∗/
/∗
Arguments:
=======
te: the type expression
Result:
=======
TypeExpr: the resulting type expression
∗/
truncate : TypeExpr → TypeExpr
truncate(tel) ≡
case tel of
TypeLiteral(literal) → tel,
TypeName(id) → tel,
TypeExprProduct(telp) →
if truncateTypeExprProduct(telp) = 〈〉
then TypeLiteral(UNIT)
else
if len truncateTypeExprProduct(telp) = 1
then hd truncateTypeExprProduct(telp)
else
TypeExprProduct(
truncateTypeExprProduct(telp))
end
end,
TypeExprSet(tes) → tel,
TypeExprList(te) → tel,
TypeExprMap(tem) → tel,
FunctionTypeExpr(te, fa, rd) →
FunctionTypeExpr(
truncate(te), fa,
mk_ResultDesc(
read_access_desc(rd),
write_access_desc(rd),
truncate(type_expr(rd)))),
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