Hi, On Fri, 16 Jan 2009, Santi Béjar wrote: > If everything works as I think (it's late night :-) with the above two lines: > > matrix[a,b,c] > matrix{d,b,c} > > the word diff would be > > matrix<RED>[<GREEN>{<RED>a<GREEN>d<RESET>,b,c<RED>]<GREEN>}<RED> So I guess that you want something like [A-Za-z0-9]+|[^A-Za-z0-9 \t]+ Note: I only want to help you finding what you actually want, I am not trying to find it for you. Ciao, Dscho