datamapper에 테이블을 추가하면 '초기화되지 않은 상수'오류가 발생합니다.

Question

내 앱에 테이블을 추가하려고하는데 다음과 같은 오류가 발생합니다. 하지만 왜 그런지 모르겠다. 내가 한 모든 것은 Recommendation 클래스를 추가하는 것이다.

class Item 
    include DataMapper::Resource 
    property :id, Serial 
    property :sortorder, Integer 
    property :title, Text 
    property :company, String 
    property :desc, Text 
    property :year, Integer 
    property :url, String 
    mount_uploader :source, ImageUploader 
end 

class Recommendations 
    include Datamapper::Resource 
    property :id, Serial 
    property :firstname, String 
    property :lastname, String 
    property :title, String 
    property :mugshot, String 
    property :text, Text 
end 

configure :development do 
    DataMapper.auto_upgrade! 
    DataMapper.finalize 
    puts "you're developing" 
end 

오류 :

15:30:27 [rerun] Joelsanden-se launched 

/Users/simpel/Sites/ruby/joelsanden-se/main.rb:48:in `<class:Recommendations>': uninitialized constant Recommendations::Datamapper (NameError) 
from /Users/simpel/Sites/ruby/joelsanden-se/main.rb:47:in `<top (required)>' 
from /Users/simpel/Sites/ruby/joelsanden-se/config.ru:19:in `require' 
from /Users/simpel/Sites/ruby/joelsanden-se/config.ru:19:in `block in <main>' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/builder.rb:55:in `instance_eval' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/builder.rb:55:in `initialize' 
from /Users/simpel/Sites/ruby/joelsanden-se/config.ru:in `new' 
from /Users/simpel/Sites/ruby/joelsanden-se/config.ru:in `<main>' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/builder.rb:49:in `eval' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/builder.rb:49:in `new_from_string' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/builder.rb:40:in `parse_file' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/server.rb:277:in `build_app_and_options_from_config' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/server.rb:199:in `app' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/server.rb:314:in `wrapped_app' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/server.rb:250:in `start' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/lib/rack/server.rb:141:in `start' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/gems/rack-1.5.2/bin/rackup:4:in `<top (required)>' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/bin/rackup:23:in `load' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/bin/rackup:23:in `<main>' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/bin/ruby_noexec_wrapper:14:in `eval' 
from /Users/simpel/.rvm/gems/ruby-2.0.0-p0/bin/ruby_noexec_wrapper:14:in `<main>' 

15:30:29 [rerun] Joelsanden-se Launch Failed 

Answer 1

당신은 오타가 - Datamapper 그래서 대신

,536의

include DataMapper::Resource 

를 사용 DataMapper

해야한다

include Datamapper::Resource