http://dev.perl.org/rfc/37.pod And if we adopt complex data structures (how complex? just wrappers for C structs, into very fast hashes) as suggested in rfc 61, we could return those special, limited pseudohashes with only the relevant names, resolvable into offsets at compile time, instead of the fully hashed hashes suggested in 37. For backwards compat, they could still return their list in array context.
