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//! Inspired by the answers to http://stackoverflow.com/q/39638363/859279, I decided to implement //! some broken traits Eq and Hash for f32. Obviously you generally shouldn't use these. But I want //! my hashing... use std::mem; use std::hash; /// To quote shepmaster (except this is an f32): /// > Basically, if you want to treat a f64 as a set of bits that have no meaning, well, we can /// > treat them as an equivalently sized bag of bits that know how to be hashed and /// > bitwise-compared. /// > Don't be surprised when one of the 16 million NaN values doesn't equal another one. #[derive(Debug, Clone, Copy)] pub struct BrokenF32(pub f32); impl BrokenF32 { fn key(&self) -> u32 { unsafe { mem::transmute(self.0) } } } impl hash::Hash for BrokenF32 { fn hash<H>(&self, state: &mut H) where H: hash::Hasher { self.key().hash(state) } } impl PartialEq for BrokenF32 { fn eq(&self, other: &Self) -> bool { self.key() == other.key() } } impl Eq for BrokenF32 {}