>>>>> "W" == Wilbert Berendsen <wbsoft / xs4all.nl> writes: W> (update 12-06-2001:) Another question: even when using a ruby array for W> the map (because of the order), will the regexp match the joined keys in W> the same order? Won't the '<' be found before the '<<'? '<<' found (in your regexp) before '<' W> But will it always be guaranteed that the keys in the regexp are matched W> on a base of 'first one found matches'? actually yes (it's like a P language) here your regexp pigeon% ruby -rjj -e '/\\>|\\<|<<|>>|<|>/.dump' Regexp `\\>|\\<|<<|>>|<|>' 0 on_failure_jump ==> 3 1 exactn "\>" (2) 2 jump_past_alt ==> 5 3 on_failure_jump ==> 6 4 exactn "\<" (2) 5 jump_past_alt ==> 8 6 on_failure_jump ==> 9 7 exactn "<<" (2) 8 jump_past_alt ==> 11 9 on_failure_jump ==> 12 10 exactn ">>" (2) 11 jump_past_alt ==> 14 12 on_failure_jump ==> 15 13 exactn "<" (1) 14 jump ==> 16 15 exactn ">" (1) 16 end pigeon% Guy Decoux