升级到 Rails 4.2 后，我很高兴尝试新集成的 Web 控制台，但我遇到了一些问题。
在 Rails 4.2 的发行说明中，它提到：“使用 Rails 4.2 生成的新应用程序现在默认带有 Web Console gem。”
由于我升级到 4.2，我认为这意味着我仍然必须在我的 Gemfile 中指定它。如果不将它添加到我的 Gemfile 中，rails 只会给我“未定义的局部变量或方法‘控制台’”，所以我认为是这样。
一旦我将 gem 'web-console', '~> 2.0' 添加到 Gemfile，并运行 rails 服务器，我现在得到：
/home/kevin/.rvm/gems/ruby-2.1.5/gems/binding_of_caller-0.7.3.pre1/lib/binding_of_caller/mri2.rb:21:in `callers': uninitialized constant RubyVM::DebugInspector (NameError)
from /home/kevin/.rvm/gems/ruby-2.1.5/gems/better_errors-2.0.0/lib/better_errors/exception_extension.rb:7:in `set_backtrace'
from /home/kevin/.rvm/gems/ruby-2.1.5@global/gems/bundler-1.7.6/lib/bundler/runtime.rb:76:in `require'
from /home/kevin/.rvm/gems/ruby-2.1.5@global/gems/bundler-1.7.6/lib/bundler/runtime.rb:76:in `block (2 levels) in require'
from /home/kevin/.rvm/gems/ruby-2.1.5@global/gems/bundler-1.7.6/lib/bundler/runtime.rb:72:in `each'
from /home/kevin/.rvm/gems/ruby-2.1.5@global/gems/bundler-1.7.6/lib/bundler/runtime.rb:72:in `block in require'
from /home/kevin/.rvm/gems/ruby-2.1.5@global/gems/bundler-1.7.6/lib/bundler/runtime.rb:61:in `each'
from /home/kevin/.rvm/gems/ruby-2.1.5@global/gems/bundler-1.7.6/lib/bundler/runtime.rb:61:in `require'
from /home/kevin/.rvm/gems/ruby-2.1.5@global/gems/bundler-1.7.6/lib/bundler.rb:133:in `require'
from /home/kevin/workspace/applications/ems-heroes/config/application.rb:6:in `<top (required)>'
from /home/kevin/.rvm/gems/ruby-2.1.5/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:78:in `require'
from /home/kevin/.rvm/gems/ruby-2.1.5/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:78:in `block in server'
from /home/kevin/.rvm/gems/ruby-2.1.5/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `tap'
from /home/kevin/.rvm/gems/ruby-2.1.5/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `server'
from /home/kevin/.rvm/gems/ruby-2.1.5/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
from /home/kevin/.rvm/gems/ruby-2.1.5/gems/railties-4.2.0/lib/rails/commands.rb:17:in `<top (required)>'
from bin/rails:4:in `require'
from bin/rails:4:in `<main>'
我用谷歌搜索并没有找到太多。任何意见是极大的赞赏。
谢谢！