久しぶりにHomebrewをupdateしたら以下のようなエラーがでて失敗し、全てのbrewコマンドが使えなくなった時の対処法です。原因は特定してないけど、おそらくOSをEl Capitanにアップデートしたせい。 takezoux2$ brew update /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require': cannot load such file -- mach (LoadError) from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/ker
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