I found the following bug in the basis List domain:
(121) -> li := [5,6,7,8,9]
(121) [5,6,7,8,9]
Type:
List(PositiveInteger)
(122) -> delete!(li,1)
(122) [6,7,8,9]
Type:
List(PositiveInteger)
(123) -> li
(123) [5,6,7,8,9]
Type:
List(PositiveInteger)
(124) -> delete!(li,1)
(124) [6,7,8,9]
Type:
List(PositiveInteger)
(125) -> delete!(li,1)
(125) [6,7,8,9]
Type:
List(PositiveInteger)
(126) -> delete!(li,1)
(126) [6,7,8,9]
Type:
List(PositiveInteger)
(127) -> delete!(li,2)
(127) [5,7,8,9]
Type:
List(PositiveInteger)
(128) -> delete!(li,2)
(128) [5,8,9]
Type:
List(PositiveInteger)
(129) -> delete!(li,2)
(129) [5,9]
Type:
List(PositiveInteger)
(130) -> delete!(li,2)
(130) [5]
The reason is in the following code:
delete!(x : %, i : Integer) ==
i < (m := minIndex x) => error "index out of range"
i = m => rest x
y := rest(x, (i - 1 - m)::NonNegativeInteger)
setrest!(y, rest(y, 2))
x
for category ListAggregate
where the case i = m (=1) does return rest x as desired, but not destructively,
while this is done for the other cases via setrest!
As destructive list changes are done via LISP operations I have to leave it to
the experts for that to fix this bug.
--
Mit freundlichen Grüßen
Johannes Grabmeier
Prof. Dr. Johannes Grabmeier
Köckstraße 1, D-94469 Deggendorf
Tel. +49-(0)-991-2979584, Tel. +49-(0)-151-681-70756
Tel. +49-(0)-991-3615-141 (d), Fax: +49-(0)-3224-192688
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