Transformation of Applicative Specifications into Imperative ...

APPENDIX C. FORMAL SPECIFICATIONS OF TRANSFORMATIONS
if pl = 〈〉 then (true, env, types)
else
let
(b, env1, types1) =
CheckPattern(hd pl, func, trans, env, types)
in
if b
then
CheckPatternList(
tl pl, func, trans, env1, types1)
else (false, env1, types)
end
end
end,
/∗Checks for transformability of a list pattern.
∗/
/∗
Arguments:
=======
lp: the list pattern
Results:
=======
Bool: true if the lis pattern can be transformed,
false otherwise
∗/
CheckListPattern :
ListPattern × FUNC × TRANS × ENV × TYPES →
Bool × ENV × TYPES
CheckListPattern(lp, func, trans, env, types) ≡
case lp of
Make_EnumeratedListPattern(elp) →
CheckOptInnerPattern(
inner_pattern(elp), func, trans, env, types),
ConcatenatedListPattern(elp, p) →
let
(b1, env1, types1) =
CheckOptInnerPattern(
inner_pattern(elp), func, trans, env,
types),
(b2, env2, types2) =
CheckPattern(p, func, trans, env1, types1)
in
(b1 ∧ b2, env2, types2)
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