pub struct StdRng(_);Expand description
The standard RNG. The PRNG algorithm in StdRng is chosen to be efficient
on the current platform, to be statistically strong and unpredictable
(meaning a cryptographically secure PRNG).
The current algorithm used is the ChaCha block cipher with 20 rounds. This may change as new evidence of cipher security and performance becomes available.
The algorithm is deterministic but should not be considered reproducible due to dependence on configuration and possible replacement in future library versions. For a secure reproducible generator, we recommend use of the rand_chacha crate directly.
Trait Implementations
sourceimpl RngCore for StdRng
impl RngCore for StdRng
sourcefn fill_bytes(&mut self, dest: &mut [u8])
fn fill_bytes(&mut self, dest: &mut [u8])
Fill dest with random data. Read more
sourceimpl SeedableRng for StdRng
impl SeedableRng for StdRng
type Seed = <ChaCha20Rng as SeedableRng>::Seed
type Seed = <ChaCha20Rng as SeedableRng>::Seed
Seed type, which is restricted to types mutably-dereferencable as u8
arrays (we recommend [u8; N] for some N). Read more
sourcefn from_seed(seed: <StdRng as SeedableRng>::Seed) -> StdRng
fn from_seed(seed: <StdRng as SeedableRng>::Seed) -> StdRng
Create a new PRNG using the given seed. Read more
sourcefn from_rng<R>(rng: R) -> Result<StdRng, Error> where
R: RngCore,
fn from_rng<R>(rng: R) -> Result<StdRng, Error> where
R: RngCore,
Create a new PRNG seeded from another Rng. Read more
sourcefn seed_from_u64(state: u64) -> Self
fn seed_from_u64(state: u64) -> Self
Create a new PRNG using a u64 seed. Read more
sourcefn from_entropy() -> Self
fn from_entropy() -> Self
impl CryptoRng for StdRng
Auto Trait Implementations
impl RefUnwindSafe for StdRng
impl Send for StdRng
impl Sync for StdRng
impl Unpin for StdRng
impl UnwindSafe for StdRng
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
impl<T> Pointable for T
impl<T> Pointable for T
sourceimpl<R> Rng for R where
R: RngCore + ?Sized,
impl<R> Rng for R where
R: RngCore + ?Sized,
sourcefn gen<T>(&mut self) -> T where
Standard: Distribution<T>,
fn gen<T>(&mut self) -> T where
Standard: Distribution<T>,
sourcefn gen_range<T, B1, B2>(&mut self, low: B1, high: B2) -> T where
T: SampleUniform,
B1: SampleBorrow<T>,
B2: SampleBorrow<T>,
fn gen_range<T, B1, B2>(&mut self, low: B1, high: B2) -> T where
T: SampleUniform,
B1: SampleBorrow<T>,
B2: SampleBorrow<T>,
Generate a random value in the range [low, high), i.e. inclusive of
low and exclusive of high. Read more
sourcefn sample<T, D>(&mut self, distr: D) -> T where
D: Distribution<T>,
fn sample<T, D>(&mut self, distr: D) -> T where
D: Distribution<T>,
Sample a new value, using the given distribution. Read more
sourcefn sample_iter<T, D>(self, distr: D) -> DistIter<D, Self, T>ⓘNotable traits for DistIter<D, R, T>impl<D, R, T> Iterator for DistIter<D, R, T> where
D: Distribution<T>,
R: Rng, type Item = T; where
D: Distribution<T>,
fn sample_iter<T, D>(self, distr: D) -> DistIter<D, Self, T>ⓘNotable traits for DistIter<D, R, T>impl<D, R, T> Iterator for DistIter<D, R, T> where
D: Distribution<T>,
R: Rng, type Item = T; where
D: Distribution<T>,
D: Distribution<T>,
R: Rng, type Item = T;
Create an iterator that generates values using the given distribution. Read more
sourcefn fill<T>(&mut self, dest: &mut T) where
T: AsByteSliceMut + ?Sized,
fn fill<T>(&mut self, dest: &mut T) where
T: AsByteSliceMut + ?Sized,
Fill dest entirely with random bytes (uniform value distribution),
where dest is any type supporting AsByteSliceMut, namely slices
and arrays over primitive integer types (i8, i16, u32, etc.). Read more
sourcefn try_fill<T>(&mut self, dest: &mut T) -> Result<(), Error> where
T: AsByteSliceMut + ?Sized,
fn try_fill<T>(&mut self, dest: &mut T) -> Result<(), Error> where
T: AsByteSliceMut + ?Sized,
Fill dest entirely with random bytes (uniform value distribution),
where dest is any type supporting AsByteSliceMut, namely slices
and arrays over primitive integer types (i8, i16, u32, etc.). Read more
sourcefn gen_bool(&mut self, p: f64) -> bool
fn gen_bool(&mut self, p: f64) -> bool
Return a bool with a probability p of being true. Read more
sourcefn gen_ratio(&mut self, numerator: u32, denominator: u32) -> bool
fn gen_ratio(&mut self, numerator: u32, denominator: u32) -> bool
Return a bool with a probability of numerator/denominator of being
true. I.e. gen_ratio(2, 3) has chance of 2 in 3, or about 67%, of
returning true. If numerator == denominator, then the returned value
is guaranteed to be true. If numerator == 0, then the returned
value is guaranteed to be false. Read more
impl<SS, SP> SupersetOf<SS> for SP where
SS: SubsetOf<SP>,
impl<SS, SP> SupersetOf<SS> for SP where
SS: SubsetOf<SP>,
fn to_subset(&self) -> Option<SS>
fn to_subset(&self) -> Option<SS>
The inverse inclusion map: attempts to construct self from the equivalent element of its
superset. Read more
fn is_in_subset(&self) -> bool
fn is_in_subset(&self) -> bool
Checks if self is actually part of its subset T (and can be converted to it).
unsafe fn to_subset_unchecked(&self) -> SS
unsafe fn to_subset_unchecked(&self) -> SS
Use with care! Same as self.to_subset but without any property checks. Always succeeds.
fn from_subset(element: &SS) -> SP
fn from_subset(element: &SS) -> SP
The inclusion map: converts self to the equivalent element of its superset.