MongoMapper：“ StandardFormBuilder”的未定义方法“ each”：String

问题描述

| 我在padrino上使用了MongoMapper，在执行任何“ 0”任务时遇到了麻烦。对于几乎所有任务，我都会收到此错误。

ethan@tardis:/var/www/sakura$ padrino rake -T
=> Executing Rake -T ...
/home/ethan/.rvm/gems/ruby-1.9.2-head/gems/mongo_mapper-0.8.6/lib/mongo_mapper/plugins/modifiers.rb:19:in `set\': undefined method `each\' for \"StandardFormBuilder\":String (NoMethodError)
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-helpers-0.9.29/lib/padrino-helpers.rb:33:in `registered\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/sinatra-1.2.6/lib/sinatra/base.rb:1200:in `block in register\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/sinatra-1.2.6/lib/sinatra/base.rb:1198:in `each\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/sinatra-1.2.6/lib/sinatra/base.rb:1198:in `register\'
    from /var/www/sakura/app/app.rb:3:in `<class:Sakura>\'
    from /var/www/sakura/app/app.rb:1:in `<top (required)>\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/reloader.rb:128:in `require\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/reloader.rb:128:in `safe_load\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:140:in `block in require_dependencies\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:138:in `each\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:138:in `require_dependencies\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/mounter.rb:125:in `locate_app_object\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/mounter.rb:21:in `initialize\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/mounter.rb:189:in `new\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/mounter.rb:189:in `mount\'
    from /var/www/sakura/config/apps.rb:34:in `<top (required)>\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/reloader.rb:128:in `require\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/reloader.rb:128:in `safe_load\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:140:in `block in require_dependencies\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:138:in `each\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:138:in `require_dependencies\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:56:in `block in load!\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:56:in `each\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/loader.rb:56:in `load!\'
    from /var/www/sakura/config/boot.rb:29:in `<top (required)>\'
    from /home/ethan/.rvm/rubies/ruby-1.9.2-head/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:55:in `require\'
    from /home/ethan/.rvm/rubies/ruby-1.9.2-head/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:55:in `require\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/cli/base.rb:51:in `block in rake\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/cli/base.rb:130:in `capture\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/lib/padrino-core/cli/base.rb:51:in `rake\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/thor-0.14.6/lib/thor/task.rb:22:in `run\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/thor-0.14.6/lib/thor/invocation.rb:118:in `invoke_task\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/thor-0.14.6/lib/thor.rb:263:in `dispatch\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/thor-0.14.6/lib/thor/base.rb:389:in `start\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/gems/padrino-core-0.9.29/bin/padrino:8:in `<top (required)>\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/bin/padrino:19:in `load\'
    from /home/ethan/.rvm/gems/ruby-1.9.2-head/bin/padrino:19:in `<main>\'

我尝试了多个Ruby版本，结果相似。这是Sinatra，MongoMapper的错误，还是什么？     

解决方法

        ActiveSupport似乎有问题。 在您的gemfile中添加：

gem \"mongo_mapper\",\"~> 0.9.1\"