Ooh thanks that’s horrible :-)
Yes I need to investigate that in more detail.
Edited to add: one option for making my assumption true might be to use fmul_fast and friends https://doc.rust-lang.org/core/intrinsics/fn.fmul_fast.html
Yes I need to investigate that in more detail.
Edited to add: one option for making my assumption true might be to use fmul_fast and friends https://doc.rust-lang.org/core/intrinsics/fn.fmul_fast.html
Instead it's "yes it's my fault that I forgot about the nonsensical concepts of positive and negative zero, and that the associative operation of addition isn't actually associative, and that addition's identity isn't actually and identity..."
Scheme has Numerical towers that automatically abstract over exact numeric representations, but instead this clearly smart engine is forced to spend mental cycles remembering and debugging this arbitrary special case logic.
Nulls, floating point, ... we really have some huge programming mistakes that have cost so much time over the years.
An no this isn't a rant on 'everybody should use scheme or Lisp, because that completely misses the point. It's that 'Worse Is Better' really is worse in the long run.
Another idea is to rely on Rust-specific optimizations: make the concrete type used by the result expressions into
enum ZeroNum {
Zero,
Num(f64),
}