Let trait Fill be implemented for element types
#1652
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These impls contradict the doc that fn fill is implemented for types which may be reinterpreted as [u8].
newpavlov
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Aug 7, 2025
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newpavlov
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Looks good to me, but I worry that it may be technically considered a breaking change. It probably should not cause any breakage in practice, so I guess it's fine.
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Yes, this is a breaking change. I'd like to start working towards the next rand version now; we may need to make a v0.9 branch. |
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CHANGELOG.mdentrySummary
This is a simpler variant (no specialization support) of #1651.
Fillimpls to types safely reinterpretable as a byte-slice. This removes additional capability gained in Replace AsByteSliceMut with Fill #940.Fillto the element type, not slice/array. This supports external impls on externally-defined types. Fixes CHANGE: AllowFillto be implemented for third-party types #1650.Motivation
This trait was added to fill a capability gap: a safe interface for fast filling of slices like
[i16]. The impls for[bool],[f32]etc. are extra complexity beyond this and unnecessary since they offer no benefit over element-wise generation in user-code.