Transformation of Applicative Specifications into Imperative ...

APPENDIX C. FORMAL SPECIFICATIONS OF TRANSFORMATIONS
else
CheckPreCondGen(
value_expr(hd cbl), func, trans, types) ∧
CheckPreCondGenCaseBranch(
tl cbl, func, trans, types)
end,
/∗Checks for transformability of a value expression.
∗/
/∗
Arguments:
=======
ve: the value expression
et: the expected type of the value expression
Results:
=====
Bool: true if the list is transformable, false
otherwise
∗/
CheckValueExpr :
ValueExpr × ExpType × TYPINGS × FUNC × TRANS ×
ENV × TYPES →
Bool × ENV × TYPES
CheckValueExpr(
ve, et, typings, func, trans, env, types) ≡
case ve of
Make_ValueLiteral(vl) →
(true, updateENV(env, et, trans), types),
Make_ValueOrVariableName(vn) →
if ∼ isinBinding(IdBinding(id(vn)), dom types)
then (true, updateENV(env, et, trans), types)
else
if
checkTRANS(
types(IdBinding(id(vn))), dom trans)
then
/∗The value expression is of the type of interest.
∗/
(isinBinding(IdBinding(id(vn)), rng env),
updateENV(env, et, trans), types)
else
/∗The value expression is not of the type of interest.
∗/
(true, updateENV(env, et, trans), types)
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