>>>>> "R" == Ralph Mason <ralph.mason / telogis.com> writes: R> What am I missing here? $_ (like $~) is a local and thread local variable. R> irb(main):001:0> $_= "ruby" R> "ruby" R> irb(main):002:0> module Kernel ; def upcase ; $_.upcase! ; end ; end Inside #upcase $_ is nil because it was never assigned. Guy Decoux