Ruby on rails 与flay相关的米制fu安装问题

嗨，我已经在运行hobo的rails 2.2系统上安装了metric_fu，但我无法运行metrics命令。这是我的日志：

$:apfcool $item rake metrics:all
(in /Users/$/Documents/apf/apfcool)
* master
/Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:171:in `process_sexp': undefined method `<' for nil:NilClass (NoMethodError)
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:309:in `[]'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:309:in `deep_each'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:318:in `each_sexp'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:315:in `each'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:315:in `each_sexp'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:308:in `deep_each'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:169:in `process_sexp'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:144:in `process'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:121:in `each'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:121:in `process'
    from /Users/$/.gem/ruby/1.8/gems/flay-1.4.0/bin/flay:10
    from /usr/bin/flay:19:in `load'
    from /usr/bin/flay:19
rake aborted!
undefined method `first' for nil:NilClass

$：apfcool$项目rake度量：全部
（在/Users/$/Documents/apf/apfcool中）
*主人
/Users/$/.gem/ruby/1.8/gems/flay-1.4.0/lib/flay.rb:171:in'process\u sexp'：未定义的方法`升级到雪豹时遇到了这个问题。我通过移除并重新安装sexp_处理器和ParseTree gems修复了它。他们做一些低级的东西，所以如果他们下面的地面移动，你需要重新安装

gem卸载sexp_处理器
宝石卸载解析树

然后：

gem安装sexp_处理器
gem安装解析树

根据您存储gem的方式，您可能希望将“sudo”放在这些命令前面