"undefined method"-error

rubyonrails-talk
1

Hi,

I'm new to rails and so far think it's great, but I'm having some major issues with a many-through relationship.

There are three tables: reporttemplates articlestemplates_reporttemplates (additional attribute "optional") articletemplates

They are connected to each other via has_many and through + belongs_to in articlestemplates_reporttemplates.

Now, I need to display all articletemplates and show, if there is a connection (entry in articlestemplates_reporttemplates) to the current reporttemplate. So in the controller I call @articletemplates = Articletemplate.find(:all, :joins=>"LEFT JOIN articletemplates_reporttemplates ON `articletemplates_reporttemplates`.articletemplate_id = `articletemplates`.id WHERE `articletemplates_reporttemplates`.reporttemplate_id = "+params[:id])

So far, everything is working. When I call <% puts YAML::dump(articletemplate.articletemplates_reporttemplates) %> in the view, it gives me: - !ruby/object:ArticletemplatesReporttemplate   attributes:     created_at: 2008-12-16 17:24:19     optional: "0"     updated_at: 2008-12-16 17:24:19     id: "1"     reporttemplate_id: "1"     articletemplate_id: "1"   attributes_cache: {}

But when I try to access the attribute "optional", I always get an error message! <% if articletemplate.articletemplates_reporttemplates.optional == 0 %> leads to "undefined method `optional' for #<Class:0x7f83e7451880>"

Why does it tell me "undefined", when one line above it tells me there is an attribute "optional"?

Any help is appreciated!

Best Regards, Daniel Süpke

2

c'mon guys, don't leave me hanging on my very first rails question here ;).

It's basically just: How can the debug output give tell me something is an object with attributes and then it doesn't let me access this attributes? Maybe it's a bug. Well, if no one has a clue I will try to find a bug tracker and post it there, but it's probably just my lack of knowledge in ruby/rails.

Regards, Daniel Süpke

3

But when I try to access the attribute "optional", I always get an error message! <% if articletemplate.articletemplates_reporttemplates.optional == 0 %> leads to "undefined method `optional' for #<Class:0x7f83e7451880>"

Why does it tell me "undefined", when one line above it tells me there is an attribute "optional"?

Assuming you're using the normal conventions,
articletemplates_reporttemplates is an array. it doesn't have an
optional attribute (but the elements inside it do)

Fred

4

Thanks a bunch, that helped. Didn't know that "---" is meant to represent an array, YAML::dump could be more intuitive there. It only told me "object", so I never even thought of an array. Well, now it works, so thanks again!