On Thu 18 Aug 2016 18:14, Mark H Weaver <m...@netris.org> writes: > As I wrote above, the current guile compiler can already do this kind of > type inference, although it does not currently do this for boxes. > we can already anticipate having native code generation in the > next couple of years, and we must keep boxes semantically simple so that > our future compiler will be able to generate good code for this very > important fundamental type.
For what it's worth, I don't see the optimization argument as weighing very heavily on this discussion. I would rather have fewer fundamental data types rather than more, in the next two years or so. I see the mid-term result here being that SRFI-111 boxes are much slower than variables. The highest performance compilation tier we can imagine would include adaptive optimization, and when it runs you can know that the variables that a bit of code uses are bound or not. Also in that case we can reasonably make any call to variable-unset! deoptimize any code that uses variables, forcing it to reoptimize later. Since variable-unset! is quite rare this is no big deal I think. Andy