Hi, I'm brand new to GHC development, and have been looking at: http://ghc.haskell.org/trac/ghc/ticket/4243 I was initially thinking of something like getopt_long_only, as per: http://linux.die.net/man/3/getopt_long however it looks like the portability of that function isn't the greatest, and from looking at rts/RtsFlags.c:procRtsOpts(...) it might not be the best solution. Unless I've missed something, it seems that the processing of each flag is independent of the others, at least once we get into procRtsOpts(...), and the processing of a flag either mutates the RtsFlags variable or results in an error. If that's not likely / wanted to change I think there are some nifty ways to abstract that, as long as function pointers aren't frowned on in the RTS code :) Since it looks like it would be a sizeable patch, should I put together a proof-of-concept and ask for feedback sooner rather than later? I'd hate to emerge from my codecave with a fully-formed but unacceptable solution. While I'm at it - does anyone have any thoughts or wishlists for a cleaned up option parser? Cheers, Dave