I have the following class:
class Question < ActiveRecord::Base
table has quiz_id, text, created_at, updated_at
belongs_to :quiz
has_many :options
validates_presence_of :text
validates_length_of :text, :within => 3…255
def to_s
text
end
end
in my tests, everything works fine. In my view, I have
<%= @question %>
which yields “ActionView::TemplateError (undefined method `to_s’ for
#Question:0x32c8d84)”
Interestingly,
<%= @question.text %> yields the appropriate text.
<%= @question.text %> yields “Question”
<%= @question.inspect %> yields values for the fields text,
created_at, and updated_at.
@question.options and @question.quiz both yield the same error as
@question.to_s
Anybody have any idea why this is happening?
-G C Novus
I meant that @question.class yielded “Question”
Hi James,
gcnovus wrote:
def to_s
<%= @question.text %> yields the appropriate text.
<%= @question.text %> yields “Question”
<%= @question.inspect %> yields values for the fields text,
created_at, and updated_at.
@question.options and @question.quiz both yield the same error as
@question.to_s
Anybody have any idea why this is happening?
My first guess would be that it’s because to_s is valid on object
attributes, not on a “complex” object. While you haven’t shown it, you
imply that you’re trying to use it on a 'complex" object (e.g.,
@question.to_s). If @questions.object and @questions.quiz would also
yield
objects, rather than object attributes, then I’d start there.
hth,
Bill
On Jul 8, 2007, at 11:27 PM, Bill W. wrote:
has_many :options
#Question:0x32c8d84)"
Anybody have any idea why this is happening?
Bill
You might also be wary of using ‘text’ as a column name since that is
a MySql type too. The definition of your to_s might work better as:
def to_s
self.text # or the new name you use to replace ‘text’
end
Or:
def to_s
read_attribute(:text) # or the new name
end
-Rob
Rob B. http://agileconsultingllc.com
[email protected]
Except . . . to_s is explicitly defined to return text. Changing that
to return read_attribute(:text) makes no difference. Nor does
changing the database column to “q_text” or something else that can’t
be interpreted as a keyword.
-Gaius
On Jul 9, 11:27 am, Matthew R. [email protected]
As an added complication, let’s say I have two quizzes in the
database, Quiz1 and Quiz2. If I load up Quiz1 first, and try to look
at it’s question1, I get the method not defined error. If I then load
up Quiz2 and try to find its question49, it doesn’t exist.
Now, here’s the really weird thing… if I flush the database and
restart the server (which re-inserts the same defaults: Quiz1 and
Quiz2), then load Quiz2 first, that one gets the error on question49,
and question1 for quiz1 doesn’t exist!
-Gaius
On Jul 9, 11:27 am, Matthew R. [email protected]
The implicit point is that <%= stuff %>
will evaluate;
returned = eval “stuff”
and add this to the html by calling “returned.to_s”
as such;
<%= @question %>
will call the .to_s method on @question.
if @question.to_s is not defined, you get an error.
The same error you’re getting.
Rob B. wrote:
On Jul 8, 2007, at 11:27 PM, Bill W. wrote:
def to_s
self.text # or the new name you use to replace ‘text’
end
Or:
def to_s
read_attribute(:text) # or the new name
end
If anyone is interested, the solution is this:
the quizzes that were being autocreated on startup weren’t valid. Why
they didn’t throw an exception I don’t know. Why they still loaded
into memory I don’t know (except that validations probably aren’t run
on retrieval). But why on Earth did this prevent the associated
objects from loading properly??? I have absolutely no clue.
Chalk one up to esoteric error messages.
-Gaius