• rich pattern matching
  • in data structures
  • function overloading with arg patterns and arbitrary guards
• bitfield expressions and matching
  • (arbitrary bits length from 1 to 64+ and endianness)
• non-preemptive memory-isolated coroutines scheduled over generic OS threads
  • async non-blocking message passing
  • fault and restart mechanics with supervisors tree
• clustering facilities
  • across isolated OS processes
  • over IP networks
    • (or at least at hardware level, eth100+ with/without RDMA)

Is any of this features too complex to implement or totally does not match with D lang computing model or compiler architecture, to not whine about adding at least a few of them into the D3?