[rules-users] Accumulate / collect

[Wolfgang Laun]

This is possible with an accumulate where you code the init/action/result
explicily. Perhaps not fully "out of the box" but a box that holds
everything would be rather big, wouldn't it? ;-)

-W

2011/11/15 Bruno Freudensprung <bruno.freudensprung at temis.com>

> **
> Hi all,
>
> There is something I can't express using "collect" or "accumulate" and I
> would like to have your opinion.
> Let's imagine I have the following types :
>
>     # a country type
> *    declare Country
>        name : String
>     end
> *
>     # a city type holding a reference to its country
> *    declare City
>        name : String
>        country : Country
>     end
> *
> Let's imagine I have all Country and City objects into the working memory.
> I want to get the set of Countries corresponding to Cities whose name
> starts with "X".
>
> I have the impression that I need a kind of (nonexistent right?) "collect"
> syntax that would look like the "accumulate" syntax (a kind of "anonymous"
> accumulate function):
>
>     # meaning I want to collect $country objects and not City objects
>     $countries : HashSet() from collect (City($name matches "X.*",
> $country : country)*, $country*)
>
> Or a home made accumulate function that builds a set of countries:
>
>     # custom "buildset" accumulate function
>     $countries : HashSet() from accumulate (City($name matches "X.*",
> $country : country), *buildset*($country))
>
> Do you see any other (possibly out of the box) solution?
>
> Many thanks in advance for your answers,
> Best regards,
>
> Bruno.
>
>
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20111115/7f3e88c1/attachment.html