Uninstall everything in local repository of gem.

Hi, all

when i type command ‘gem list’ it will show me the list as the following:

*** LOCAL GEMS ***

abstract (1.0.0)
actionmailer (3.0.9)
actionpack (3.0.9)
activemodel (3.0.9)
activerecord (3.0.9)
activeresource (3.0.9)
activesupport (3.0.9)
arel (2.0.10)
builder (2.1.2)
bundler (1.0.15)

So, i want to uninstall everything in the list , in other words, remove everything in local repository of gems,
but i don’t want uninstall it one by one with that original command.