Question

UPDATE:

I’ve put this in my person class

  has_many :things, :dependent => :destroy do 
    def [](kind)
      where("kind = ?", kind.to_s)
    end
  end

but when I invoke <Person Instance>.things[:table], I get this error:

undefined method `where' for #<Class:0x111dc3ba8>

ORIGINAL QUESTION:

I have a person, who has_many things.
I’d like to be able to do something like:

<Person Instance>.things[:table]

that would be defined similar to

def things[](arg)
    self.things.find(:first, :conditions => ["kind = ?", arg.to_s])
end

currently, that method gives me this error:

syntax error, unexpected '[', expecting '\n' or ';'

So, how do I properly define things[]?

Answer 1

What you’re looking for are called association extensions in rails.
Read about it here

Your implementation might look something like:

has_many :things do
  def [](kind)
    where(:kind => kind)
  end
end