cygwinの再インストール

ぐふぅ．
この間入れて動いていた nicodown.rb が今度は動かない．
mechanize-0.7.3 に undefined method があるとかエラー出る．
なんでだー．

/usr/lib/ruby/gems/1.8/gems/mechanize-0.7.3/lib/www/mechanize/file.rb:46:in `initialize': undefined method `path' for #<WWW::Mechanize::File:0x7fc8ec20> (NoMethodError)
	from /usr/lib/ruby/gems/1.8/gems/mechanize-0.7.3/lib/www/mechanize/page.rb:30:in `initialize'
	from /usr/lib/ruby/gems/1.8/gems/mechanize-0.7.3/lib/www/mechanize.rb:174:in `new'
	from /usr/lib/ruby/gems/1.8/gems/mechanize-0.7.3/lib/www/mechanize.rb:174:in `get'
	from /usr/lib/ruby/gems/1.8/gems/nicovideo-0.1.1/lib/nicovideo/base.rb:49:in `call'
	from /usr/lib/ruby/gems/1.8/gems/nicovideo-0.1.1/lib/nicovideo/base.rb:49:in `try'
	from /usr/lib/ruby/gems/1.8/gems/nicovideo-0.1.1/lib/nicovideo/base.rb:45:in `get'
	from /usr/lib/ruby/gems/1.8/gems/mechanize-0.7.3/lib/www/mechanize.rb:194:in `get_file'
	from /usr/lib/ruby/gems/1.8/gems/nicovideo-0.1.1/lib/nicovideo/videopage.rb:40:in `video'
	from /usr/lib/ruby/gems/1.8/gems/nicovideo-0.1.1/lib/nicovideo/videopage.rb:34:in `flv'
	from nicodown.rb:31
	from nicodown.rb:31:in `open'
	from nicodown.rb:31
	from /usr/lib/ruby/gems/1.8/gems/nicovideo-0.1.1/lib/nicovideo/base.rb:75:in `watch'
	from nicodown.rb:30
	from nicodown.rb:29:in `each'
	from nicodown.rb:29