Change:
// It turns out the safety issues with sNaN were overblown! Hooray! unsafe { mem::transmute(v) } } <ins> /// Return the memory representation of this floating point number as a byte array in /// big-endian (network) byte order. /// /// # Examples /// /// ``` /// #![feature(float_to_from_bytes)] /// let bytes = 12.5f32.to_be_bytes(); /// assert_eq!(bytes, [0x41, 0x48, 0x00, 0x00]); /// ``` #[unstable(feature = "float_to_from_bytes", issue = "60446")] #[inline] pub fn to_be_bytes(self) -> [u8; 4] { self.to_bits().to_be_bytes() } /// Return the memory representation of this floating point number as a byte array in /// little-endian byte order. /// /// # Examples /// /// ``` /// #![feature(float_to_from_bytes)] /// let bytes = 12.5f32.to_le_bytes(); /// assert_eq!(bytes, [0x00, 0x00, 0x48, 0x41]); /// ``` #[unstable(feature = "float_to_from_bytes", issue = "60446")] #[inline] pub fn to_le_bytes(self) -> [u8; 4] { self.to_bits().to_le_bytes() } /// Return the memory representation of this floating point number as a byte array in /// native byte order. /// /// As the target platform's native endianness is used, portable code /// should use [`to_be_bytes`] or [`to_le_bytes`], as appropriate, instead. /// /// [`to_be_bytes`]: #method.to_be_bytes /// [`to_le_bytes`]: #method.to_le_bytes /// /// # Examples /// /// ``` /// #![feature(float_to_from_bytes)] /// let bytes = 12.5f32.to_ne_bytes(); /// assert_eq!( ///     bytes, ///     if cfg!(target_endian = "big") { ///         [0x41, 0x48, 0x00, 0x00] ///     } else { ///         [0x00, 0x00, 0x48, 0x41] ///     } /// ); /// ``` #[unstable(feature = "float_to_from_bytes", issue = "60446")] #[inline] pub fn to_ne_bytes(self) -> [u8; 4] { self.to_bits().to_ne_bytes() } /// Create a floating point value from its representation as a byte array in big endian. /// /// # Examples /// /// ``` /// #![feature(float_to_from_bytes)] /// let value = f32::from_be_bytes([0x41, 0x48, 0x00, 0x00]); /// assert_eq!(value, 12.5); /// ``` #[unstable(feature = "float_to_from_bytes", issue = "60446")] #[inline] pub fn from_be_bytes(bytes: [u8; 4]) -> Self { Self::from_bits(u32::from_be_bytes(bytes)) } /// Create a floating point value from its representation as a byte array in big endian. /// /// # Examples /// /// ``` /// #![feature(float_to_from_bytes)] /// let value = f32::from_le_bytes([0x00, 0x00, 0x48, 0x41]); /// assert_eq!(value, 12.5); /// ``` #[unstable(feature = "float_to_from_bytes", issue = "60446")] #[inline] pub fn from_le_bytes(bytes: [u8; 4]) -> Self { Self::from_bits(u32::from_le_bytes(bytes)) } /// Create a floating point value from its representation as a byte array in big endian. /// /// As the target platform's native endianness is used, portable code /// likely wants to use [`from_be_bytes`] or [`from_le_bytes`], as /// appropriate instead. /// /// [`from_be_bytes`]: #method.from_be_bytes /// [`from_le_bytes`]: #method.from_le_bytes /// /// # Examples /// /// ``` /// #![feature(float_to_from_bytes)] /// let value = f32::from_ne_bytes(if cfg!(target_endian = "big") { ///     [0x41, 0x48, 0x00, 0x00] /// } else { ///     [0x00, 0x00, 0x48, 0x41] /// }); /// assert_eq!(value, 12.5); /// ``` #[unstable(feature = "float_to_from_bytes", issue = "60446")] #[inline] pub fn from_ne_bytes(bytes: [u8; 4]) -> Self { Self::from_bits(u32::from_ne_bytes(bytes)) } </ins> }

Discussion:
These feel appropriate to add for completeness, and would simply chain or with the appropriate integer method. I'll add a PR soon. <!-- TRIAGEBOTSTART --<!-- TRIAGEBOTASSIGNSTART --This issue has been assigned to via . <!-- TRIAGEBOTASSIGNDATASTARTTRIAGEBOTASSIGNDATAEND --<!-- TRIAGEBOTASSIGNEND --<!-- TRIAGEBOTEND --
Byte order conversions on floats themselves make little sense. The conversions should be done before float’s functions are called.
Err, I misread the proposal the first time around...
claim