FLR

The overloading of '[' and '[[' on FLFleet to be used when selecting down the metier and catch levels, returning shole FLFleet objects or single metiers/catches, interferes with normal use of '[' for subsetting along quant, year,...

One option is to use subset for the later type of selection, but it still breaks expected behaviour.

Another option, tricky to implement, is to try to dispatch for one or the other according to the selection level (indices for dims 3:6 are always going to be for units, seasons and iters), and value (indices for 1:22 could be matched first with dimnames and then with metier/catch names). This still leaves room for problem if names coincide, and what to do if selection is done by number.