I have recently moved from RVM to Rbenv and when attempting to execute rails I am getting an error like the one below
Pauls-Air:~ $ rails rbenv: rails: comma
After installing a gem via the command line in a ruby version you have to execute rbenv rehash as described in the docs here and here
rbenv rehash
For example:
$ rbenv install 2.2.0 $ gem install bundler $ rbenv rehash $ gem install rails $ rbenv rehash