On Thu, Nov 5, 2009 at 6:15 PM, brian
<briand@aracnet.com> wrote:
On Nov 5, 2009, at 8:26 AM, Jason Dagit wrote:
Haskell knows when I have a list of Doubles, you know, because it's strongly typed.
Then it proceeds to box them. Huh ?
Imagine a computation which will yield a Double if evaluated, but has not yet been evaluated. How do you store that in the list?
"Necessary" is a strong word within formal/mathematical communities. If you mean it in that sense, then I'm not sure it's necessary. My (incomplete) understanding is that no one has a better way than boxing that has as wide applicability as boxing. Perhaps there are techniques that work better. My guess is that they are either 1) special cases; or 2) have yet to be discovered. I wonder if perhaps supercompilation or perhaps whole program optimizations will eventually be able to eliminate much of the boxing we have today. Strictness analysis has done a lot to remove boxing but it is not perfect due to the halting problem.
Jason