On Monday, 14 August 2017 at 01:52:16 UTC, Johnson Jones wrote:
pretty simply, trying to convert a floating point to a string in a ctfe function and it thinks that it is too complex to do in a ctfe, really?
It uses a C function to do the conversion, which is not available at compile time since CTFE can't run extern functions.
And it is a LOT harder to do than you might think which is why it still uses the C function - implementing one in D is legit pretty complex.
When I first saw this too, I figured it must be simple to slap something together, even if it is horribly inefficient and doesn't work everywhere... and I ended up giving up after spending a few hours on it too. If you search the web, you get academic papers describing it, eeek.
Of course, it might be reasonable to port one of the C implementations directly... but even that is a fairly big job (and you might as well just call the C function itself for all but CTFE cases) - the GNU one is 1,300 lines, for example. And that has an incompatible license with the rest of druntime!
