On Friday, 4 March 2016 at 16:45:42 UTC, Andrei Alexandrescu
wrote:
Currently we have a very useful stride() function that allows
spanning a random access range with a specified step, e.g. 0,
3, 6, 9, ... for step 3.
I've run some measurements recently and it turns out a
compile-time-known stride is a lot faster than a variable. So I
was thinking to improve Stride(R) to take an additional
parameter: Stride(R, size_t step = 0). If step is 0, then use a
runtime-valued stride as until now. If nonzero, Stride should
use that compile-time step.
Takers?
This makes me wonder if something like iota would benefit from a
similar optimization. It's frequently the case that all of the
arguments to iota are known at compile time. Now, iota isn't
wrapping another range (unlike stride), so maybe that would make
the difference, and iota wouldn't particularly benefit from
having its arguments be template arguments, but I have to wonder.
- Jonathan M Davis
