Question

按照本教程，我试图了解Sinatra ruby框架：

http://net.tutsplus.com/tutorials/ruby/singing-with-sinatra-the-recall-app-2/

然而，在运行gem安装并在test.rb中编写一个简单的sinatra服务器后如下：

require 'sinatra'
require 'datamapper'

get '/' do 
  "Hello, World!"
end

但是当我运行命令ruby test.rb时，我收到以下错误：

/usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': no such file to load -- datamapper (LoadError)
    from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from datamapper_test.rb:2:in `<main>'
glenn@ubuntu:~/Dropbox/Repositories/sandbox/sinatra$ ruby datamapper_test.rb 
/usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': no such file to load -- datamapper (LoadError)
    from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from test.rb:3:in `<main>'

好像它无法找到datamapper gem。我该如何解决这个问题？

编辑：使用ruby 1.9.2

编辑（再次）：gem list的{parital}输出：

data_mapper (1.2.0)
data_objects (0.10.8)
datamapper (1.2.0)
devise (1.4.5)
directory_watcher (1.4.0)
dm-aggregates (1.2.0)
dm-constraints (1.2.0)
dm-core (1.2.0)
dm-do-adapter (1.2.0)
dm-migrations (1.2.0)
dm-serializer (1.2.1)
dm-sqlite-adapter (1.2.0)
d    m-timestamps (1.2.0)
dm-transactions (1.2.0)
dm-types (1.2.1)
dm-validations (1.2.0)
do_sqlite3 (0.10.8)
sinatra (1.3.2, 1.2.6)
sqlite3 (1.3.5, 1.3.4)
sqlite3-ruby (1.3.3)

Answer 1

您需要require 'data_mapper'，而不是datamapper。

请注意，有一个datamapper gem和一个data_mapper gem，但它们是相同的，只是名称不同。您需要在其中使用data_mapper作为库名。

据我所知，datamapper是data_mapper的完整副本：

$ diff -r data_mapper-1.2.0/ datamapper-1.2.0/
diff -r data_mapper-1.2.0/Rakefile datamapper-1.2.0/Rakefile
21c21
< GEM_NAME         = 'data_mapper'
---
> GEM_NAME         = 'datamapper'

Answer 2

终端中的

gem install datamapper可能有帮助:) 但是你还需要一个数据库和一个适配器，你会想要以某种方式使用gem。祝你好运，与dm + sinatra玩得开心！

ruby datamapper不会加载

2 个答案: