Iterators/vectors (was: [Biocorba-l] BSANE and bioCORBA)

[Juha Muilu]

Michael Dickson wrote:
> 
> I'll add my "vote" for the original patterns.  We discussed precisely
> the issues Antoine raised during the initial discussion which is why we
> settled on the patterns we did.
> 
> If I had to change anything about it (and we don't :)  I'd replace the
> typesafe iterators with one generic one.  Its a small point but the
> other methods generates lots of stubs and skeletons (for languages that
> have them).  I generally prefer type safety but in practice this proved
> to be a bit of a pain.  So the code you'd likely see would look like:

I agree with you. We have found current type safe iterators bit pain as
well.

> 
> Object obj;
> while (someIterator.next(&obj)) {
>   TypedObj tobj = TypedObjHelper.narrow(obj);
>   tobj.dostuff();
> }
> 
> Instead of:
> 
> TypedObject obj;
> while (someIterator.next(&tobj)) {
>   tobj.dostuff();
> }
> 
> I don't feel religious about it but I'd clearly prefer it.
> 
> Mike
> 
> Juha Muilu wrote:
> 
> >Hi Antoine,
> >Nice to have you on the list!
> >
> >So we will keep the iterator/list pattern as used in the BSA.
> >
> >I have found it quite good to implement and use.
> >
> >
> >Antoine van Gelder wrote:
> >
> >>On 31 May 2001 23:39:19 +0100, Martin Senger wrote:
> >>
> >>>  Although I thing that it is not big issue I feel that implementation
> >>>with 'out' parameter and returning boolean is easier and also it saves one
> >>>network call.
> >>>   I do not like raising any Exception as a "normal" behaviour - that
> >>>makes the codeclumsy and less readable.
> >>>
> >>Iterator patterns that return bool are much cleaner as it allows for
> >>code such as:
> >>
> >>Object obj;
> >>while (someIterator.next(&obj)) {
> >>  obj.dostuff();
> >>}
> >>
> >>Instead of:
> >>
> >>while (someIterator.has_more()) {
> >>  Object obj = someIterator.theObject();
> >>}
> >>
> >>Which is heavier on both network calls and object constructor calls.
> >>
> >>Or even worse if I understood Brad correctly:
> >>
> >>try {
> >>  while (someIterator.hasNext()) {
> >>    SomeObj obj = someIterator.the_object();
> >>  }
> >>} catch (SomeException) {
> >>  // extremely cpu expensive way of ending a loop adding huge
> >>  // overhead to even the simplest algorithm not to mention
> >>  // the pain you cause in terms of memory management for
> >>  // c++ developers.
> >>}
> >>
> >> - a
> >>
> >>_______________________________________________
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> >>Biocorba-l@biocorba.org
> >>http://www.biocorba.org/mailman/listinfo/biocorba-l
> >>

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