Information listed in GEM PATHS

Ruby
1

The Ruby environment can be seen with

gem env

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Where are the paths (listed under GEM PATHS) stored, so that “gem env” can display them?

I’m asking, because I would like to remove one of the paths. The picture above shows the environment on my private computer. On my business computer, the second path is a network path, where I do not have write permission. Before contacting the IT I would like to change the path to a location where I have permission.

By the way: I’m using the portable version of ruby 2.6.6 on Windows.

2

They appear to be stored in the environment variables GEM_HOME and GEM_PATH.

Calling:

$ gem help env

Includes the following:

RubyGems’ default local repository can be overridden with the GEM_PATH and GEM_HOME environment variables. GEM_HOME sets the default repository to install into. GEM_PATH allows multiple local repositories to be searched for gems.

3

They appear to be stored in the environment variables GEM_HOME and GEM_PATH .

What exactly do you mean with "environment variables’? In my windows environment there are no variables GEM_HOME and GEM_PATH.

Calling ENV inside irb leads to:

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So, the question is still valid: How does the command gem env know what do list under “GEM PATHS”?

The first item is c:/PortableApps/Ruby/Ruby26/lib/ruby/gems/2.6.0, which is the default folder of my Ruby.

But how is the second item C:/Users/ped/.gem/ruby/2.6.0 created? Probably by doing on the fly this:

File.join(ENV['HOMEDRIVE'], ENV['HOMEPATH'], '.gem/ruby/2.6.0'])

4

I mean Environment Variables - Win32 apps | Microsoft Learn
When using windows at work, I can access them through the control panel.

They are what ENV is accessing: class ENV - RDoc Documentation
So your ‘HOMEPATH’, ‘HOMEDRIVE’ are (windows) environment variables.

What is the value of ENV['GEM_PATH']

5

The value of ENV[‘GEM_PATH’] is nil:

Pic01

This makes sence, because the object ENV has no key GEM_PATH.

I tried to illustrate my question with several screenshots, but unfortunately as a new user I am only allowed to insert one picture in an answer. So i have to move on with only text instead of screenshots.

IT has mapped my HOMEDRIVE (usually c:) to a network directory.

ap ENV leads to:

“HOME” => “H:/”
“HOMEDRIVE” => “H:”
“HOMEPATH” => “\”

But directly on this HOMEDRIVE I don’t have write access. In HOMEDRIVE they created a directory Documents where I have write access. On H itself I have no write permissions.

gem env leads to:

GEM PATHS:

  • <path/to/my/ruby/>/lib/ruby/gems/2.6.0
  • H:/.gem/ruby/2.6.0

But there is no directory H:/.gem/ruby/2.6.0. For this reason I wondered how the directory gets into GEM PATHS. It would be great if I could tell ruby to use instead H:/Documents/.gem/...