2007/10/28, Sean O'Halpin <sean.ohalpin / gmail.com>: > On 10/28/07, Robert Klemme <shortcutter / googlemail.com> wrote: > > > > irb(main):007:0> array = %w{apple banana apple orange} > > => ["apple", "banana", "apple", "orange"] > > irb(main):008:0> array.inject(Hash.new(0)) {|ha,e| > > ha[e]+=1;ha}.delete_if {|k,v| v==1}.keys > > => ["apple"] > > > Succint ~and~ efficient! Thanks! > Do you have a mail filter checking for any posts > containing 'inject'? :) I don't need that since most of them were written by me. :-) (slight exaggeration) *chuckle* Kind regards robert