I have several versions of a Ruby gem:
$ gem list
rjb (1.3.4, 1.3.3, 1.1.9)
How can I remove old versions but keep the most recent?
# remove all old versions of the gem
gem cleanup rjb
# choose which ones you want to remove
gem uninstall rjb
# remove version 1.1.9 only
gem uninstall rjb --version 1.1.9
# remove all versions less than 1.3.4
gem uninstall rjb --version '<1.3.4'