bundle exec

Run the command in context of the bundle
$ bundle exec [--keep-file-descriptors] <command>


--keep-file-descriptors: For Ruby versions less than 2.0, keeps non-standard file descriptors on Kernel#exec

This command executes the command, making all gems specified in the Gemfile(5) available to require in Ruby programs. Essentially, if you would normally have run something like rspec spec/my_spec.rb, and you want to use the gems specified in the Gemfile and installed via bundle install, you should run bundle exec rspec spec/my_spec.rb. Note that bundle exec does not require that an executable is available on your shell's $PATH.
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