Sorry to sound like a broken record, but we can’t reach a decision without a design. I don’t know what this feature is supposed to be doing.
We try to work by consensus, but it’s not 100% required. Daniel Lee has final authority on the math lib and I have final authority on the langauge. I’m still not even sure if there are implications for the language of including a complex type.
I don’t know how @seantalts or @syclik feel about this, but I’d strongly prefer to not include speculative work commented out in our releasead code.
Instead, I’d suggest working on a branch. That’s what we’ve done with MPI and GPU development as it was converging toward a final design. And both of those are finally about to launch. This shouldn’t be as complicated as those two in terms of builds, etc., but it’s in many ways a bigger design decision as the hard parts of the GPU and MPI design were internal, not user-facing.