我有三个模型，分别是Page，AdminUser和Section：
class Page < ActiveRecord::Base
attr_accessible :name, :position, :permalink
belongs_to :subject
has_many :sections
has_and_belongs_to_many :editors, :class_name => "AdminUser"
end
class AdminUser < ActiveRecord::Base
attr_accessible :first_name, :last_name, :username
has_and_belongs_to_many :pages
scope :named, lamda {|first,last| where(:first_name => first, :last_name => last)}
end
class Section < ActiveRecord::Base
belongs_to :page
end
通过页面，用户和章节的这些迁移：
class CreatePages < ActiveRecord::Migration
def change
create_table :pages do |t|
t.references :subject
t.string "name"
t.string "permalink"
t.integer "position"
t.boolean "visible", :default => false
t.timestamps
end
puts "*** About to add an index ***"
add_index("pages", "subject_id")
add_index("pages", "permalink")
end
end
class CreateUsers < ActiveRecord::Migration
def change
create_table :users do |t|
t.string "first_name", :limit => 25
t.string "last_name", :limit => 50
t.string "email", :default => "" , :null => false
t.string "password", :limit => 40
t.timestamps
end
end
end
class CreateSections < ActiveRecord::Migration
def change
create_table :sections do |t|
t.string "name"
t.integer "position"
t.boolean "visible", :default => false
t.string "content_type"
t.text "content"
t.timestamps
end
puts "*** About to add an index ***"
add_index("sections", "name")
end
end
在尝试使用rails控制台为AdminUser创建新用户的过程中，我得到此Object不支持#inspect错误：
1.9.3p125 :001 > page = Page.find(1)
Page Load (0.7ms) SELECT `pages`.* FROM `pages` WHERE `pages`.`id` = 1 LIMIT 1
=> #<Page id: 1, subject_id: 1, name: "First Page", permalink: "first", position: 1, visible: false, created_at: "2012-06-01 15:14:50", updated_at: "2012-06-01 15:14:50">
1.9.3p125 :002 > page.editors
(Object doesn't support #inspect)
=>
编辑在控制台中执行page.editors会抛出此错误：
1.9.3p125 :003 > page.editors
ArgumentError: Unknown key: inverse_of
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/core_ext/hash/keys.rb:44:in `block in assert_valid_keys'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/core_ext/hash/keys.rb:43:in `each_key'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/core_ext/hash/keys.rb:43:in `assert_valid_keys'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/builder/association.rb:33:in `validate_options'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/builder/association.rb:24:in `build'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/builder/collection_association.rb:23:in `build'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/autosave_association.rb:139:in `build'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/builder/has_and_belongs_to_many.rb:8:in `build'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/builder/collection_association.rb:13:in `build'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations.rb:1600:in `has_and_belongs_to_many'
from /Users/aditya/simple_cms/app/models/admin_user.rb:4:in `<class:AdminUser>'
from /Users/aditya/simple_cms/app/models/admin_user.rb:1:in `<top (required)>'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:469:in `load'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:469:in `block in load_file'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:639:in `new_constants_in'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:468:in `load_file'
... 12 levels...
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:554:in `get'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:588:in `constantize'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/inheritance.rb:111:in `block in compute_type'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/inheritance.rb:109:in `each'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/inheritance.rb:109:in `compute_type'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/reflection.rb:172:in `klass'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/association.rb:117:in `klass'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/association.rb:165:in `find_target?'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/collection_association.rb:332:in `load_target'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/collection_proxy.rb:44:in `load_target'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/activerecord-3.2.3/lib/active_record/associations/collection_proxy.rb:87:in `method_missing'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/railties-3.2.3/lib/rails/commands/console.rb:47:in `start'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/railties-3.2.3/lib/rails/commands/console.rb:8:in `start'
from /Users/aditya/.rvm/gems/ruby-1.9.3-p125@global/gems/railties-3.2.3/lib/rails/commands.rb:41:in `<top (required)>'
from script/rails:6:in `require'
我被困在这里。我该如何解决这个问题？
答案 0 :(得分：1)
在您的AdminUser模型中尝试此has_and_belongs_to_many :pages, :inverse_of => :editors我认为应该是问题。