Rails core - Sep 2007 - has_many :through and access to the the through record

I have not see a way to directly access the through record when
creating a new has_many :through association.  It would seem like I
have overlooked something, but in the meantime I created a patch to
allow for it.

http://dev.rubyonrails.org/attachment/ticket/8478
http://dev.rubyonrails.org/attachment/ticket/8478/adding_to_has_many_through_yields_the_created_through_association.diff

Example:

class Post < ActiveRecord::Base
  has_many :tags
  has_many :taggings, :through => :tags
end

Post.find(:first).tags << Tag.find(:first) do |through_association|
  ... # through_association is the created Tagging record
end


--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Core" group.
To post to this group, send email to rubyonrails-core@googlegroups.com
To unsubscribe from this group, send email to
rubyonrails-core-unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/rubyonrails-core?hl=en
-~----------~----~----~----~------~----~------~--~---

On 9/17/07, foomanchoo <johngweir@gmail.com>
wrote:
>
>
> Post.find(:first).tags << Tag.find(:first) do |through_association|
>   ... # through_association is the created Tagging record
> end

Really interesting syntax. Can''t say it''s intuitive, but
definitely useful.
Do we have alternatives?

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Core" group.
To post to this group, send email to rubyonrails-core@googlegroups.com
To unsubscribe from this group, send email to
rubyonrails-core-unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/rubyonrails-core?hl=en
-~----------~----~----~----~------~----~------~--~---

> I have not see a way to directly access the through record when
> creating a new has_many :through association.  It would seem like I
> have overlooked something, but in the meantime I created a patch to
> allow for it.
The :through part of those associations is really just an optimisation
to avoid having to write:

@tag.taggings.map(&:post)

If you need access to the tagging instances, just use @tag.taggings
instead of @tag.posts
> http://dev.rubyonrails.org/attachment/ticket/8478
>
http://dev.rubyonrails.org/attachment/ticket/8478/adding_to_has_many_through_yields_the_created_through_association.diff
>
> Example:
>
> class Post < ActiveRecord::Base
>   has_many :tags
>   has_many :taggings, :through => :tags
> end
>
> Post.find(:first).tags << Tag.find(:first) do |through_association|
>   ... # through_association is the created Tagging record
> end
>
>
> >
>

-- 
Cheers

Koz

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Core" group.
To post to this group, send email to rubyonrails-core@googlegroups.com
To unsubscribe from this group, send email to
rubyonrails-core-unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/rubyonrails-core?hl=en
-~----------~----~----~----~------~----~------~--~---

> The :through part of those associations is really just an optimisation
> to avoid having to write:
>
> @tag.taggings.map(&:post)
>
> If you need access to the tagging instances, just use @tag.taggings
> instead of @tag.posts
True, but I don''t see how this helps in referencing the newly created
association.

where is the Tagging record in the below?
post = Post.find(:first).tags << Tag.find(:first)

I would like a reliable and easy method of referencing the created
association, which the patch provides and does so without presenting
any compatibility issues.  However there might be another way, which I
have not thought of.


--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Core" group.
To post to this group, send email to rubyonrails-core@googlegroups.com
To unsubscribe from this group, send email to
rubyonrails-core-unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/rubyonrails-core?hl=en
-~----------~----~----~----~------~----~------~--~---

On Sep 19, 2007, at 5:13 PM, foomanchoo wrote:
>
>> The :through part of those associations is really just an  
>> optimisation
>> to avoid having to write:
>>
>> @tag.taggings.map(&:post)
>>
>> If you need access to the tagging instances, just use @tag.taggings
>> instead of @tag.posts
>
> True, but I don''t see how this helps in referencing the newly
created
> association.
>
> where is the Tagging record in the below?
> post = Post.find(:first).tags << Tag.find(:first)
>
> I would like a reliable and easy method of referencing the created
> association, which the patch provides and does so without presenting
> any compatibility issues.  However there might be another way, which I
> have not thought of.

What''s wrong with this:

   tagging = Post.find(:first).taggings.create :tag => Tag.find(:first)




--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Core" group.
To post to this group, send email to rubyonrails-core@googlegroups.com
To unsubscribe from this group, send email to
rubyonrails-core-unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/rubyonrails-core?hl=en
-~----------~----~----~----~------~----~------~--~---