On Mon, Jul 17, 2017 at 12:01:48PM -0700, H. S. Teoh via Digitalmars-d-learn
wrote:
[...]
> template sumOfLengths(A...)
> if (A.length > 0)
> {
> static if (A.length == 1)
> enum sumOfLengths = A[0].length;
> else
> enum sumOfLengths = A[0].length + sumOfLengths!(A[1 ..
> $]);
> }
>
> T[sumOfLengths!StaticArrays] append(StaticArrays...)(StaticArrays
> arrays)
> if (/* insert static array constraints here */)
> {
> typeof(return) result = void;
> size_t offset = 0;
> foreach (a; arrays)
> {
> result[offset .. offset + a.length] = a[];
> }
> return result;
> }
[...]
Hmm, since we already have sumOfLengths available at compile-time, what
about:
T[sumOfLengths!StaticArrays] append(StaticArrays...)(StaticArrays
arrays)
if (allSatisfy!(isStaticArray, StaticArrays))
{
typeof(return) result = void;
foreach (i, a; 0 .. arrays.length)
{
enum offset = sumOfLengths!(arrays[0 .. i]);
result[offset .. offset + a.length] = a[];
}
return result;
}
T
--
People say I'm indecisive, but I'm not sure about that. -- YHL, CONLANG
