ArgumentError - 调用.all时参数的数量错误

Question

I am very new to RoR and although I have done quite an extensive amount of searching on StackOverflow and Google, I can't seem to solve this problem.

In my controller, I have the following code to initialize the @coupon_categories instance variable, and continuously get this error in my index method:

wrong number of arguments (0 for 1)

This is my CouponCategoryController file:

class CouponCategoryController < ApplicationController

   # Implemented when user input taken
   def index
     @coupon_categories = CouponCategory.all
   end

   def new
     @coupon_category = CouponCategory.new(params[:coupon_category])
   end

coupon_category.rb:

class CouponCategory < ActiveRecord::Base

  has_many :coupons, :dependent => destroy # destroys coupons dependent on coupon_category  

end

Any insight would be greatly appreciated! Thank you :)

Edit: Here is my view file, along with the full error messages. index.html.erb:

<h1> Create A Coupon Category! </h1>

<%= form_for :coupon_category do |f| %>
 Category Name: <%= f.text_field "name" %><br />
 Category expiration date (YYYY-MM-DD): <%= f.text_field "date_expired" %><br />
     <%= f.submit %>
<% end %>

<%= render :partial => 'coupon/index' %>

Full error message:

ArgumentError in CouponCategoryController#index

wrong number of arguments (0 for 1)

app/models/coupon_category.rb:2:in `<class:CouponCategory>'
app/models/coupon_category.rb:1:in `<top (required)>'
app/controllers/coupon_category_controller.rb:5:in `index'

Thank you for your help!

Answer 1

The problem may be

has_many :coupons, :dependent => destroy

The destroy should be a symbol, :destroy .

has_many :coupons, :dependent => :destroy