Zhenning Guan wrote:
> I gem install someone so can use the someone, but how I read the someone
> source code?

The simplest way is just to look at the installed lib files. Look in 
ruby/lib/gems/1.8/gems/name_of_gem/lib. Where exactly your ruby/lib 
directory is will depend on your OS, but maybe something like 
C:/ruby/lib on Windows, or /usr/lib, /usr/local/lib or /opt/lib on 
Unix-ish systems.

Most gem-based software is open-source, so you should be able to find 
the code on wherever the project is hosted. Find out the project's 
homepage (often on Rubyforge) and go to 'Files' or 'Download'. Good 
projects will offer their code as a zip or .tar.gz download.

A .gem file is just a .zip file, so you can also unzip it and look 
inside for the source code.

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