On Thursday, 1 November 2018 at 00:01:04 UTC, Stefan Koch wrote:
On Wednesday, 31 October 2018 at 23:14:08 UTC, Bastiaan Veelo
wrote:
Currently, BitArray is not usable at compile time, so you
cannot do
```
enum e = BitArray([1, 1, 1, 0]);
```
This gives
/dlang/dmd/linux/bin64/../../src/phobos/std/bitmanip.d(1190):
Error: `bts` cannot be interpreted at compile time, because
it has no available source code
IIUC, that is because `bts` comes from core.bitop but no
source code is there. I am guessing these are filled in by
compiler intrinsics or the like, and they are unavailable at
CT, correct?
I suppose that alternative implementations of `btc`, `bts`,
`btr`, `bsf` and `bt` could exist that do not use the runtime
that could be used if(__ctfe) in the implementation of
BitArray, that would make the above code work. Is this
feasible? Is there precedent in phobos? Are there
complications?
Thanks!
Oh that ... actually I can fix that with a small patch to dmd.
Tell me which version are you using and I'll make it for you.
Cheers,
Stefan
Thank you, Stefan. At the moment we are using latest stable dmd,
v2.082.1. I expect to switch to ldc or gdc at a later time. I
don't think we'll be patching the compiler, support in the
mainline compilers would be much preferable. It is not a blocker
either, we can wait as long as it takes and meanwhile use module
level BitArrays like
```
immutable BitArray e;
static this()
{
e = BitArray([1, 1, 1, 0]);
}
```
It just seemed like a fixable limitation to me, hence my question
here. Shall we start with a feature request?
Bastiaan.
