23 Feb
2015
23 Feb
'15
11:09 p.m.
Exactly :).
In Fame, there is a FMMultivalueLink hierarchy that implement many to one
and many to many relations. This implementation exists since before slots
and now we should reimplement them with slots. It will make the code so
much nicer :).
Anyone interested in picking this up?
Cheers,
Doru
On Mon, Feb 23, 2015 at 10:34 PM, Ben Coman <btc(a)openinworld.com> wrote:
I haven't played with the relation example yet,
but will real soon. Just
some initial thoughts...
I like RelationSlot. To me association seems one-way while a relation is
two-way.
btw, Is there some reason to not match the syntax of the often cited paper
"Flexible Object Layout" ?
I see one advantage is that its easier to read all the slot names
vertically aligned.
Object subclass: #SlotExampleMovie
slots: {
#name.
#year.
#director => ToOneRelationSlot opposite: #directedMovies class:
#SlotExamplePerson.
#actors => ToManyRelationSlot opposite: #actedInMovies class: #SlotExamplePerson.
}
classVariables: { }
category: 'SlotAssociations-Tests-Example'
Also maybe an alternative slot class name so that it reads more like a
sentence... "#director related to one #directedMovies in class
#SlotExamplePerson"
Object subclass: #SlotExampleMovie
slots: {
#name.
#year.
#director => RelatedToOne inverse: #directedMovies inClass:
#SlotExamplePerson.
#actors => RelatedToMany inverse: #actedInMovies inClass: #SlotExamplePerson.
}
classVariables: { }
category: 'SlotAssociations-Tests-Example'
Or even...
Object subclass: #SlotExampleMovie
slots: {
#name.
#year.
#director => OneRelatedTo many: #directedMovies inClass:
#SlotExamplePerson.
#actors => ManyRelatedTo many: #actedInMovies inClass: #SlotExamplePerson.
}
classVariables: { }
category: 'SlotAssociations-Tests-Example'
cheers -ben
On Tue, Feb 24, 2015 at 2:33 AM, Jan van de Sandt <jvdsandt(a)gmail.com>
wrote:
--
www.tudorgirba.com
"Every thing has its own flow"
On Mon, Feb 23, 2015 at 9:59 AM, Marcus Denker <marcus.denker(a)inria.fr>
wrote:
Very nice! Can I add this to Pharo4 as an example?
Sure, cool!
On 21 Feb 2015, at 21:11, Jan van de Sandt
<jvdsandt(a)gmail.com> wrote:
Today I experimented a little with the new Slots feature of Pharo 4.0.
As an
example I implemented support for associations/relationships.
My idea is that at first we add these things as
examples, and then later
take the examples and distill a library of
generally useful slots.
That sounds like a good approach to get familiar with these kind of new
features.
Some things I can do to improve the Example
- Add an option to make one side of the association readonly. In most
situations I think it's a good idea to update an association only from one
side to keep things simple.
- Whats a better name AssociationSlot or RelationSlot? I'm not sure
- As Stéphane said, isn't there a nicer way to declare the associations?
- Better error handling
Jan.