undefined method ‘c’ error

rubyonrails-talk
1

Hey all,

I'm getting an undefined method 'c' error. I'm in the students controller, and I'm trying to find the book associated with the student, and then take that book's id_number and assign the room's id to it and then save the book:

def student_test   @student = (params[:id] and Student.find(params[:id])) || Student.new   run_sequence :testize end

def test_finalize   Student.transaction do     @student.update_attributes(params[:student]) and @student.test! if (params[:student])

    room = Room.new

    room.room_num = 5     room.save

    c = Student.for_test && @student #@student.for_test doesn't work, but I'm trying to apply named_scope to @student to get book associated with the selected student.     Book.c.id_num = room.id     Book.save

  end end

Student model:

named_scope :for_test, :include => :book, :conditions => [:first, "book.location_id == site_id"]

The idea is to find the book associated with the student via the location and then pass the room id into that book's id_num.

Thanks for any response.

2

John Merlino wrote:

Given I see lots of issues with your code, I'm going to answer your question directly.

    Book.c.id_num = room.id

This line references a class method on the Book class named c. Something like this:

class Book   def self.c     ...   end end

This could also be defined using a named_scope, which essentially becomes a class method:

class Book   named_scope :c, ... end

So if Book has no c method defined, and nothing creates one at runtime, then Ruby gives you the error you're seeing.

3

I changed it around:

def student_test @student = Student.for_test.find(params[:id]) if params[:id] @student ||= Student.new run_sequence :testize end

def test_finalize Student.transaction do if (params[:student]) and @student.update_attributes(params[:student])   @student.test! end

room = Room.new(:room_num => 5) room.save

book = @student.book book.id_num = room.id book.save end end

But still get this error message: undefined method `id_num='

4

Can you show the full error message?

5

Sharagoz -- wrote:

Can you show the full error message?

In the code, I actually have: book = @student.books not book = @student.book

This is because in Student model, I have has_many :books

And named_scope:   named_scope :for_test,        :include => :books, :conditions => ["books.location_id = site_id && books.book_state_id = 5"]

And this is the full error: NoMethodError in StudentsController#student_test undefined method `id_num=' for #<Class:0x106036ea0>