Re: ItemList

"so we would just have to remove the subtype relationship to CreativeWork.”

Would this be necessary?  Creating an [unordered or] ordered collection of things or items, is a creative act.  OK you may not use many of the CreativeWork properties but being able identify the creator, about-ness, created/modified dates, etc. could be useful.

There is a definite need for Collections (as CreativeWorks) see some of the examples in the now moribund Collection proposal <http://www.w3.org/wiki/WebSchemas/Collection>, the core proposal for hasPart & isPartOf were subsumed into the Periodicals, Articles and Multi-volume Works proposal.

The current ItemList Type proposal it not far off from my point of view.
My only concern is with the proposed ListItem Type.  By introducing an item property to link to the item in the list, we are introducing an indirection between the list and it’s members, making it a slightly complex task to identify all the items on a list for example, and making the markup more complex.

As an alternative I would suggest a model where ListItem (without an item property) could be used as an alternativeType on any Thing.  This would enable the items to be directly referenced from ItemList properties.  Finally I would add a sortValue or listOrderValue to ListItem so that ordering could be defined on a per item basis.

If consensus comes down on the side of needing a non-CreativeWork ItemList, I then believe we would need a total of 4 classes:

  *   Collection - subClassOf CreativeWork using hasPart to identify collection members
  *   ItemList - As per current proposal
  *   ListItem - With the changes identified above
  *   OrderedCollection -subClassOf Collection & ItemList

~Richard

On 13 May 2014, at 20:35, Jarno van Driel <jarnovandriel@gmail.com<mailto:jarnovandriel@gmail.com>> wrote:

Got it, thanks. And I can live with that just fine.

Now I also was just looking at the periodicals proposal (https://www.w3.org/wiki/WebSchemas/Periodicals,_Articles_and_Multi-volume_Works) and wondered if there's any danger of ItemList having some overlap with the proposed @hasPart property. @hasPart's description in that proposal says: "A related CreativeWork that is included either logically or physically in this CreativeWork; for example, things in a collection, parts in a multi-part work, or articles in a periodical or publication issue."

Now I could be wrong here but "things in a collection, parts in a multi-part work" both could be expressed with the properties of ItemList as well. So I don't know if that should be investigated further as well.


2014-05-13 21:26 GMT+02:00 Jason Douglas <jasondouglas@google.com<mailto:jasondouglas@google.com>>:
Those are only there because it inherits from CreativeWork.  If people want to use ItemList for all ordered lists, than we need to move that inheritance down the chain, which is what Justin is proposing.  So only EditorialItemList would inherit CreativeWork (and ItemList), while ItemList would not.


On Tue May 13 2014 at 12:19:44 PM, Jarno van Driel <jarnovandriel@gmail.com<mailto:jarnovandriel@gmail.com>> wrote:
And then add an EditorialItemList type...

Might I ask why we would need such a type, if ItemList keeps it @author and @publisher properties wouldn't that suffice to express it's an editorialized list?


2014-05-13 21:01 GMT+02:00 Justin Boyan <jaboyan@google.com<mailto:jaboyan@google.com>>:

And then add an EditorialItemList type which inherited from both ItemList and CreativeWork, to meet the "Fodor's Top 10 Pizza Restaurants in NYC" use case.


On Tue May 13 2014 at 2:49:50 PM, martin.hepp@ebusiness-unibw.org<mailto:martin.hepp@ebusiness-unibw.org> <martin.hepp@ebusiness-unibw.org<mailto:martin.hepp@ebusiness-unibw.org>> wrote:
If I remember correctly, the proposed modification would make ItemList more generally usable for any kind of ordered collection, so we would just have to remove the subtype relationship to CreativeWork.


On 13 May 2014, at 20:20, Jason Douglas <jasondouglas@google.com<mailto:jasondouglas@google.com>> wrote:

> ItemList inherits from CreativeWork and I believe is intended to be for "editorialized lists".  Top 10 lists, etc.  A list of Breadcrumbs or BlogPosts seem in scope, but that's not currently how the schema is connected.
>
> As mentioned in other threads, I think we need a different mechanism for collections more generally.  Probably something more like the approach that was taken with Roles.
>
> On Tue May 13 2014 at 11:04:51 AM, Markus Lanthaler <markus.lanthaler@gmx.net<mailto:markus.lanthaler@gmx.net>> wrote:
> On Tuesday, May 13, 2014 6:56 PM, Dan Brickley wrote:
> > Yes, let's get ItemList back on track. We got this far previously:
> >
> > https://www.w3.org/wiki/WebSchemas/ItemList
>
> I asked this question already while ago but didn't get any answers, so I'll ask again. How is ItemList intended to be used? Can it be used as value for arbitrary properties that can be expected to take multiple values? For example, can I link a http://schema.org/Blog to an ItemList via the http://schema.org/blogPost property? Or isn't that how it is intended to be used?
>
> --
> Markus Lanthaler
> @markuslanthaler
>
>
>
>