gen_range(a, b) -> gen_range(a..b) and gen_range(a..=b)
#1003
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vks
changed the title
gen_range(a, b) -> gen_range(a..b) and gen_range(a..=b)
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The only failure is a spurious network error. |
src/rng.rs
Outdated
| fn gen_range<T: SampleUniform, B1, B2>(&mut self, low: B1, high: B2) -> T | ||
| fn gen_range<T, R>(&mut self, range: R) -> T | ||
| where | ||
| B1: SampleBorrow<T> + Sized, | ||
| B2: SampleBorrow<T> + Sized, | ||
| T: SampleUniform, | ||
| R: RangeBounds<T> | ||
| { | ||
| T::Sampler::sample_single(low, high, self) | ||
| use core::ops::Bound; | ||
| if let Bound::Included(low) = range.start_bound() { | ||
| match range.end_bound() { | ||
| Bound::Excluded(high) => T::Sampler::sample_single(low, high, self), | ||
| Bound::Included(high) => T::Sampler::sample_single_inclusive(low, high, self), | ||
| Bound::Unbounded => panic!("invalid upper bound"), | ||
| } | ||
| } else { | ||
| panic!("invalid lower bound"); | ||
| } |
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We shouldn't have to use run-time look-ups and panics. Can we do something like: where R: Into<Uniform<T>>?
No, really we need a specific trait for "sample single":
trait SampleSingle<X> {
fn sample_single(self) -> X;
}
impl<X: SampleUniform> SampleSingle<X> for Range<X> { .. }
impl<X: SampleUniform> SampleSingle<X> for RangeInclusive<X> { .. }There was a problem hiding this comment.
Yes, we would have to define such a trait if we want to avoid the lookup. Alternatively, we could inline gen_range and hope the lookup gets optimized away. What do you prefer?
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I added an implementation using static dispatch in the last commit. It required a new public trait that we may want to hide with #[doc(hidden)] to avoid users implementing it to add support for other range types.
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What do you think @newpavlov? Overall it seems more useful to expose the trait (sometimes users do want to extend generic APIs).
Sorry, this should probably be rebased and squashed. |
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I'm not sure how to work around |
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I think that's probably fine. Anyone who knows of the |
This includes a specialized implementation for integers.
This adds support for `Rng::range(a..b)` and `Rng::range(a..=b)`, replacing `Rng::range(a, b)`. `a` and `b` must now implement `PartialEq`. This is a breaking change. In most cases, replacing `Rng::gen_range(a, b)` with `Rng::gen_range(a..b)` should be enough, however type annotations may be necessary, and `a` and `b` can no longer be references or SIMD types. SIMD types are still supported by `UniformSampler::sample_single`. Some clippy warnings were fixed as well.
Replaces and closes #821.