Sorry, if I appeared as I tried to sell you something. > No, Scala cannot optimize all forms of tail recursion (such as mutually tail-recursive functions). In

Sorry, if I appeared as I tried to sell you something. > No, Scala cannot optimize all forms of tail recursion (such as mutually tail-recursive functions). In that case, you have to use scala.util.control.TailCalls to do it via trampolines. I guess we are just nick-picking each other here. :-) I think be both understand what the compiler can do, cannot do, what it does automatically and what not. Have you seen the Complex implementation which uses an underlying Long as Floats? (Sounds ugly but seems to work quite nicely.) The biggest problem at the moment is putting value types in an array. Currently it seems like some ugly clutch/work-around ill be used. I hope SIP-15 gets either rejected or delayed until there is a better solution, Because the difference between an array of references and an array of primitives really matters imho.