[gobo-eiffel-develop] Errors caught by gelint in XM_XPATH classes

[Eric B. <er...@go...>]

Gelint reports the following errors:

[VUAR-2] class XM_XPATH_ARRAY_LIST_ITERATOR (33,25): the 1-th actual 
argument (of type 'NONE') does not conform to the corresponding formal 
argument (of type 'G') of feature `has' in class DS_ARRAYED_LIST.
----
[VUAR-2] class XM_XPATH_ARRAY_LIST_ITERATOR (46,25): the 1-th actual 
argument (of type 'NONE') does not conform to the corresponding formal 
argument (of type 'G') of feature `has' in class DS_ARRAYED_LIST.
----
[VUAR-2] class XM_XPATH_ARRAY_LIST_ITERATOR (205,21): the 1-th actual 
argument (of type 'NONE') does not conform to the corresponding formal 
argument (of type 'G') of feature `has' in class DS_ARRAYED_LIST.
----
[VUAR-2] class XM_XPATH_REVERSE_ARRAY_LIST_ITERATOR (33,25): the 1-th 
actual argument (of type 'NONE') does not conform to the corresponding 
formal argument (of type 'G') of feature `has' in class DS_ARRAYED_LIST.
----
[VUAR-2] class XM_XPATH_REVERSE_ARRAY_LIST_ITERATOR (46,25): the 1-th 
actual argument (of type 'NONE') does not conform to the corresponding 
formal argument (of type 'G') of feature `has' in class DS_ARRAYED_LIST.
----
[VUAR-2] class XM_XPATH_REVERSE_ARRAY_LIST_ITERATOR (174,21): the 1-th 
actual argument (of type 'NONE') does not conform to the corresponding 
formal argument (of type 'G') of feature `has' in class DS_ARRAYED_LIST.
----

One way to solve this problem is to use inline agents ;-)))
Anyway, the assertions are obviously wrong, it should be:

   no_void_item: not a_list.has (Void)
                 ^^^
Probably not caught earlier because of the bug in gexace.

OK, I can feel the fact that you don't want to use inline
agents. So, there are several other solutions.

1) Add a routine `has_default' in class DS_SEARCHABLE.

2) Add a routine `default_item: G' in your class and
    call: not a_list.has (default_item). But this will
    not be practical for assertions in creation routines.

3) Use KL_ANY_ROUTINES.same_objects:
     not a_list.there_exists (agent ANY_.same_objects (?, Void))

Solution 3 is the one which will work without any additional
code.

PS: I would tend to avoid declaring the generic parameter
as 'reference G' because it is not part of ECMA Eiffel is
I remember correctly.

-- 
Eric Bezault
mailto:er...@go...
http://www.gobosoft.com