I''ve got an application that I''m working on where I have a
System model
that I want to add to arbitrary logical Groups (a System can be part of
multiple groups and a Group is made up of one or more Systems).
I''ve got it set up like this:
class Affiliation < ActiveRecord::Base
belongs_to :systems, :class_name => ''system'',
:foreign_key =>
''system_id''
belongs_to :groups, :class_name => ''group'', :foreign_key
=> ''group_id''
end
class Group < ActiveRecord::Base
has_many :affiliations, :dependent => true
has_many :systems, :through => :affiliations
end
class System < ActiveRecord::Base
has_many :affiliations, :dependent => true
has_many :groups, :through => :affiliations
end
when I do this (in my add action in my GroupsController:
group = Group.find(params[:group], :limit => 1)
system = System.find(params[:system], :limit => 1)
group.systems << system
I get an ArgumentError: wrong number of arguments.
the stack trace is:
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/base.rb:1360:in
`system''
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/base.rb:1360:in
`compute_type''
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/reflection.rb:125:in
`send''
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/reflection.rb:125:in
`klass''
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/associations/has_many_through_association.rb:115:in
`find_target''
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/associations/association_proxy.rb:131:in
`load_target''
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/associations/association_proxy.rb:122:in
`method_missing''
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/associations/has_many_through_association.rb:108:in
`method_missing''
#{RAILS_ROOT}/app/controllers/groups_controller.rb:20:in `add''
any ideas?
Thanks!
...spike
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The problem is that if you tell AR that the class name is ''Foo'', it will try and evaluate ''Foo'' to get the constant. Unfortunately when you try and eval ''system'' then you end up calling the system function. You class name is System (and Group in the other case), so you shouldn''t be telling AR that the class names are system & group. Also unless there''s other stuff you''re not showing us you don''t need class_name => ''system'', :foreign_key => ''system_id'' - those are the defaults. Fred -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Well, originally I didn''t specify the class or foreign_key and I get this NameError: uninitialized constant Group::Systems. I added those directives when I got that errror. so I guess you''re saying I should rename my Systems model... the only question is what another name would be. that''s gonna require some thought. you think that''s what''s causing the weirdness? Thanks! -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Spike Grobstein wrote:> Well, originally I didn''t specify the class or foreign_key and I get > this NameError: uninitialized constant Group::Systems. I added those > directives when I got that errror. > > so I guess you''re saying I should rename my Systems model... the only > question is what another name would be. that''s gonna require some > thought. > > you think that''s what''s causing the weirdness? >Ah, I misread slightly. Your belong_to should be belong_to :system & belong_to :group. (not belong_to :systems). specifying the class name would have worked if you''d supplied System instead of system. Fred -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
oh man, thanks! it works! duhh... I can''t believe I did that. I also renamed my System model to Machine to avoid potential conflicts later. thanks, again! -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---