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| author | garhve <git@garhve.com> | 2022-12-20 11:04:25 +0800 |
|---|---|---|
| committer | garhve <git@garhve.com> | 2022-12-20 11:04:25 +0800 |
| commit | 369d11587339ce74f8ebc76f2607fe55545eaf7d (patch) | |
| tree | 4b25c6f7e3aca08a90b25950f4f8e4430c4294bc /rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rng.rs.html | |
| parent | 0f1b6d015243e55a38b1c1b7e8af66668e4e794d (diff) | |
Build small project following the book
Diffstat (limited to 'rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rng.rs.html')
| -rw-r--r-- | rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rng.rs.html | 1203 |
1 files changed, 1203 insertions, 0 deletions
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href="https://www.rust-lang.org/favicon.ico"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../rand/index.html"> + <img src="https://www.rust-lang.org/logos/rust-logo-128x128-blk.png" alt="logo"></a><form class="search-form"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> +<span id="2">2</span> +<span id="3">3</span> +<span id="4">4</span> +<span id="5">5</span> +<span id="6">6</span> +<span id="7">7</span> +<span id="8">8</span> +<span id="9">9</span> +<span id="10">10</span> +<span id="11">11</span> +<span id="12">12</span> +<span id="13">13</span> +<span id="14">14</span> +<span id="15">15</span> +<span id="16">16</span> +<span id="17">17</span> +<span id="18">18</span> +<span id="19">19</span> +<span id="20">20</span> +<span id="21">21</span> +<span id="22">22</span> +<span id="23">23</span> +<span id="24">24</span> +<span id="25">25</span> +<span id="26">26</span> +<span id="27">27</span> +<span id="28">28</span> +<span id="29">29</span> +<span id="30">30</span> +<span id="31">31</span> +<span id="32">32</span> +<span id="33">33</span> +<span id="34">34</span> +<span id="35">35</span> +<span id="36">36</span> +<span id="37">37</span> +<span id="38">38</span> +<span id="39">39</span> +<span 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id="562">562</span> +<span id="563">563</span> +<span id="564">564</span> +<span id="565">565</span> +<span id="566">566</span> +<span id="567">567</span> +<span id="568">568</span> +<span id="569">569</span> +<span id="570">570</span> +<span id="571">571</span> +<span id="572">572</span> +<span id="573">573</span> +<span id="574">574</span> +<span id="575">575</span> +<span id="576">576</span> +<span id="577">577</span> +<span id="578">578</span> +<span id="579">579</span> +<span id="580">580</span> +<span id="581">581</span> +<span id="582">582</span> +<span id="583">583</span> +<span id="584">584</span> +<span id="585">585</span> +<span id="586">586</span> +<span id="587">587</span> +<span id="588">588</span> +<span id="589">589</span> +<span id="590">590</span> +<span id="591">591</span> +<span id="592">592</span> +<span id="593">593</span> +<span id="594">594</span> +<span id="595">595</span> +<span id="596">596</span> +<span id="597">597</span> +<span id="598">598</span> +<span id="599">599</span> +<span id="600">600</span> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// Copyright 2013-2017 The Rust Project Developers. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! [`Rng`] trait + +</span><span class="kw">use </span>rand_core::{Error, RngCore}; +<span class="kw">use </span><span class="kw">crate</span>::distributions::uniform::{SampleRange, SampleUniform}; +<span class="kw">use </span><span class="kw">crate</span>::distributions::{<span class="self">self</span>, Distribution, Standard}; +<span class="kw">use </span>core::num::Wrapping; +<span class="kw">use </span>core::{mem, slice}; + +<span class="doccomment">/// An automatically-implemented extension trait on [`RngCore`] providing high-level +/// generic methods for sampling values and other convenience methods. +/// +/// This is the primary trait to use when generating random values. +/// +/// # Generic usage +/// +/// The basic pattern is `fn foo<R: Rng + ?Sized>(rng: &mut R)`. Some +/// things are worth noting here: +/// +/// - Since `Rng: RngCore` and every `RngCore` implements `Rng`, it makes no +/// difference whether we use `R: Rng` or `R: RngCore`. +/// - The `+ ?Sized` un-bounding allows functions to be called directly on +/// type-erased references; i.e. `foo(r)` where `r: &mut dyn RngCore`. Without +/// this it would be necessary to write `foo(&mut r)`. +/// +/// An alternative pattern is possible: `fn foo<R: Rng>(rng: R)`. This has some +/// trade-offs. It allows the argument to be consumed directly without a `&mut` +/// (which is how `from_rng(thread_rng())` works); also it still works directly +/// on references (including type-erased references). Unfortunately within the +/// function `foo` it is not known whether `rng` is a reference type or not, +/// hence many uses of `rng` require an extra reference, either explicitly +/// (`distr.sample(&mut rng)`) or implicitly (`rng.gen()`); one may hope the +/// optimiser can remove redundant references later. +/// +/// Example: +/// +/// ``` +/// # use rand::thread_rng; +/// use rand::Rng; +/// +/// fn foo<R: Rng + ?Sized>(rng: &mut R) -> f32 { +/// rng.gen() +/// } +/// +/// # let v = foo(&mut thread_rng()); +/// ``` +</span><span class="kw">pub trait </span>Rng: RngCore { + <span class="doccomment">/// Return a random value supporting the [`Standard`] distribution. + /// + /// # Example + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// + /// let mut rng = thread_rng(); + /// let x: u32 = rng.gen(); + /// println!("{}", x); + /// println!("{:?}", rng.gen::<(f64, bool)>()); + /// ``` + /// + /// # Arrays and tuples + /// + /// The `rng.gen()` method is able to generate arrays (up to 32 elements) + /// and tuples (up to 12 elements), so long as all element types can be + /// generated. + /// When using `rustc` ≥ 1.51, enable the `min_const_gen` feature to support + /// arrays larger than 32 elements. + /// + /// For arrays of integers, especially for those with small element types + /// (< 64 bit), it will likely be faster to instead use [`Rng::fill`]. + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// + /// let mut rng = thread_rng(); + /// let tuple: (u8, i32, char) = rng.gen(); // arbitrary tuple support + /// + /// let arr1: [f32; 32] = rng.gen(); // array construction + /// let mut arr2 = [0u8; 128]; + /// rng.fill(&mut arr2); // array fill + /// ``` + /// + /// [`Standard`]: distributions::Standard + </span><span class="attribute">#[inline] + </span><span class="kw">fn </span>gen<T>(<span class="kw-2">&mut </span><span class="self">self</span>) -> T + <span class="kw">where </span>Standard: Distribution<T> { + Standard.sample(<span class="self">self</span>) + } + + <span class="doccomment">/// Generate a random value in the given range. + /// + /// This function is optimised for the case that only a single sample is + /// made from the given range. See also the [`Uniform`] distribution + /// type which may be faster if sampling from the same range repeatedly. + /// + /// Only `gen_range(low..high)` and `gen_range(low..=high)` are supported. + /// + /// # Panics + /// + /// Panics if the range is empty. + /// + /// # Example + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// + /// let mut rng = thread_rng(); + /// + /// // Exclusive range + /// let n: u32 = rng.gen_range(0..10); + /// println!("{}", n); + /// let m: f64 = rng.gen_range(-40.0..1.3e5); + /// println!("{}", m); + /// + /// // Inclusive range + /// let n: u32 = rng.gen_range(0..=10); + /// println!("{}", n); + /// ``` + /// + /// [`Uniform`]: distributions::uniform::Uniform + </span><span class="kw">fn </span>gen_range<T, R>(<span class="kw-2">&mut </span><span class="self">self</span>, range: R) -> T + <span class="kw">where + </span>T: SampleUniform, + R: SampleRange<T> + { + <span class="macro">assert!</span>(!range.is_empty(), <span class="string">"cannot sample empty range"</span>); + range.sample_single(<span class="self">self</span>) + } + + <span class="doccomment">/// Sample a new value, using the given distribution. + /// + /// ### Example + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// use rand::distributions::Uniform; + /// + /// let mut rng = thread_rng(); + /// let x = rng.sample(Uniform::new(10u32, 15)); + /// // Type annotation requires two types, the type and distribution; the + /// // distribution can be inferred. + /// let y = rng.sample::<u16, _>(Uniform::new(10, 15)); + /// ``` + </span><span class="kw">fn </span>sample<T, D: Distribution<T>>(<span class="kw-2">&mut </span><span class="self">self</span>, distr: D) -> T { + distr.sample(<span class="self">self</span>) + } + + <span class="doccomment">/// Create an iterator that generates values using the given distribution. + /// + /// Note that this function takes its arguments by value. This works since + /// `(&mut R): Rng where R: Rng` and + /// `(&D): Distribution where D: Distribution`, + /// however borrowing is not automatic hence `rng.sample_iter(...)` may + /// need to be replaced with `(&mut rng).sample_iter(...)`. + /// + /// # Example + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// use rand::distributions::{Alphanumeric, Uniform, Standard}; + /// + /// let mut rng = thread_rng(); + /// + /// // Vec of 16 x f32: + /// let v: Vec<f32> = (&mut rng).sample_iter(Standard).take(16).collect(); + /// + /// // String: + /// let s: String = (&mut rng).sample_iter(Alphanumeric) + /// .take(7) + /// .map(char::from) + /// .collect(); + /// + /// // Combined values + /// println!("{:?}", (&mut rng).sample_iter(Standard).take(5) + /// .collect::<Vec<(f64, bool)>>()); + /// + /// // Dice-rolling: + /// let die_range = Uniform::new_inclusive(1, 6); + /// let mut roll_die = (&mut rng).sample_iter(die_range); + /// while roll_die.next().unwrap() != 6 { + /// println!("Not a 6; rolling again!"); + /// } + /// ``` + </span><span class="kw">fn </span>sample_iter<T, D>(<span class="self">self</span>, distr: D) -> distributions::DistIter<D, <span class="self">Self</span>, T> + <span class="kw">where + </span>D: Distribution<T>, + <span class="self">Self</span>: Sized, + { + distr.sample_iter(<span class="self">self</span>) + } + + <span class="doccomment">/// Fill any type implementing [`Fill`] with random data + /// + /// The distribution is expected to be uniform with portable results, but + /// this cannot be guaranteed for third-party implementations. + /// + /// This is identical to [`try_fill`] except that it panics on error. + /// + /// # Example + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// + /// let mut arr = [0i8; 20]; + /// thread_rng().fill(&mut arr[..]); + /// ``` + /// + /// [`fill_bytes`]: RngCore::fill_bytes + /// [`try_fill`]: Rng::try_fill + </span><span class="kw">fn </span>fill<T: Fill + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>T) { + dest.try_fill(<span class="self">self</span>).unwrap_or_else(|<span class="kw">_</span>| <span class="macro">panic!</span>(<span class="string">"Rng::fill failed"</span>)) + } + + <span class="doccomment">/// Fill any type implementing [`Fill`] with random data + /// + /// The distribution is expected to be uniform with portable results, but + /// this cannot be guaranteed for third-party implementations. + /// + /// This is identical to [`fill`] except that it forwards errors. + /// + /// # Example + /// + /// ``` + /// # use rand::Error; + /// use rand::{thread_rng, Rng}; + /// + /// # fn try_inner() -> Result<(), Error> { + /// let mut arr = [0u64; 4]; + /// thread_rng().try_fill(&mut arr[..])?; + /// # Ok(()) + /// # } + /// + /// # try_inner().unwrap() + /// ``` + /// + /// [`try_fill_bytes`]: RngCore::try_fill_bytes + /// [`fill`]: Rng::fill + </span><span class="kw">fn </span>try_fill<T: Fill + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>T) -> <span class="prelude-ty">Result</span><(), Error> { + dest.try_fill(<span class="self">self</span>) + } + + <span class="doccomment">/// Return a bool with a probability `p` of being true. + /// + /// See also the [`Bernoulli`] distribution, which may be faster if + /// sampling from the same probability repeatedly. + /// + /// # Example + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// + /// let mut rng = thread_rng(); + /// println!("{}", rng.gen_bool(1.0 / 3.0)); + /// ``` + /// + /// # Panics + /// + /// If `p < 0` or `p > 1`. + /// + /// [`Bernoulli`]: distributions::Bernoulli + </span><span class="attribute">#[inline] + </span><span class="kw">fn </span>gen_bool(<span class="kw-2">&mut </span><span class="self">self</span>, p: f64) -> bool { + <span class="kw">let </span>d = distributions::Bernoulli::new(p).unwrap(); + <span class="self">self</span>.sample(d) + } + + <span class="doccomment">/// 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`. + /// + /// See also the [`Bernoulli`] distribution, which may be faster if + /// sampling from the same `numerator` and `denominator` repeatedly. + /// + /// # Panics + /// + /// If `denominator == 0` or `numerator > denominator`. + /// + /// # Example + /// + /// ``` + /// use rand::{thread_rng, Rng}; + /// + /// let mut rng = thread_rng(); + /// println!("{}", rng.gen_ratio(2, 3)); + /// ``` + /// + /// [`Bernoulli`]: distributions::Bernoulli + </span><span class="attribute">#[inline] + </span><span class="kw">fn </span>gen_ratio(<span class="kw-2">&mut </span><span class="self">self</span>, numerator: u32, denominator: u32) -> bool { + <span class="kw">let </span>d = distributions::Bernoulli::from_ratio(numerator, denominator).unwrap(); + <span class="self">self</span>.sample(d) + } +} + +<span class="kw">impl</span><R: RngCore + <span class="question-mark">?</span>Sized> Rng <span class="kw">for </span>R {} + +<span class="doccomment">/// Types which may be filled with random data +/// +/// This trait allows arrays to be efficiently filled with random data. +/// +/// Implementations are expected to be portable across machines unless +/// clearly documented otherwise (see the +/// [Chapter on Portability](https://rust-random.github.io/book/portability.html)). +</span><span class="kw">pub trait </span>Fill { + <span class="doccomment">/// Fill self with random data + </span><span class="kw">fn </span>try_fill<R: Rng + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, rng: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><(), Error>; +} + +<span class="macro">macro_rules! </span>impl_fill_each { + () => {}; + (<span class="macro-nonterminal">$t</span>:ty) => { + <span class="kw">impl </span>Fill <span class="kw">for </span>[<span class="macro-nonterminal">$t</span>] { + <span class="kw">fn </span>try_fill<R: Rng + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, rng: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="kw">for </span>elt <span class="kw">in </span><span class="self">self</span>.iter_mut() { + <span class="kw-2">*</span>elt = rng.gen(); + } + <span class="prelude-val">Ok</span>(()) + } + } + }; + (<span class="macro-nonterminal">$t</span>:ty, $(<span class="macro-nonterminal">$tt</span>:ty,)<span class="kw-2">*</span>) => { + <span class="macro">impl_fill_each!</span>(<span class="macro-nonterminal">$t</span>); + <span class="macro">impl_fill_each!</span>($(<span class="macro-nonterminal">$tt</span>,)<span class="kw-2">*</span>); + }; +} + +<span class="macro">impl_fill_each!</span>(bool, char, f32, f64,); + +<span class="kw">impl </span>Fill <span class="kw">for </span>[u8] { + <span class="kw">fn </span>try_fill<R: Rng + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, rng: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><(), Error> { + rng.try_fill_bytes(<span class="self">self</span>) + } +} + +<span class="macro">macro_rules! </span>impl_fill { + () => {}; + (<span class="macro-nonterminal">$t</span>:ty) => { + <span class="kw">impl </span>Fill <span class="kw">for </span>[<span class="macro-nonterminal">$t</span>] { + <span class="attribute">#[inline(never)] </span><span class="comment">// in micro benchmarks, this improves performance + </span><span class="kw">fn </span>try_fill<R: Rng + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, rng: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="kw">if </span><span class="self">self</span>.len() > <span class="number">0 </span>{ + rng.try_fill_bytes(<span class="kw">unsafe </span>{ + slice::from_raw_parts_mut(<span class="self">self</span>.as_mut_ptr() + <span class="kw">as </span><span class="kw-2">*mut </span>u8, + <span class="self">self</span>.len() * mem::size_of::<<span class="macro-nonterminal">$t</span>>() + ) + })<span class="question-mark">?</span>; + <span class="kw">for </span>x <span class="kw">in </span><span class="self">self </span>{ + <span class="kw-2">*</span>x = x.to_le(); + } + } + <span class="prelude-val">Ok</span>(()) + } + } + + <span class="kw">impl </span>Fill <span class="kw">for </span>[Wrapping<<span class="macro-nonterminal">$t</span>>] { + <span class="attribute">#[inline(never)] + </span><span class="kw">fn </span>try_fill<R: Rng + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, rng: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="kw">if </span><span class="self">self</span>.len() > <span class="number">0 </span>{ + rng.try_fill_bytes(<span class="kw">unsafe </span>{ + slice::from_raw_parts_mut(<span class="self">self</span>.as_mut_ptr() + <span class="kw">as </span><span class="kw-2">*mut </span>u8, + <span class="self">self</span>.len() * mem::size_of::<<span class="macro-nonterminal">$t</span>>() + ) + })<span class="question-mark">?</span>; + <span class="kw">for </span>x <span class="kw">in </span><span class="self">self </span>{ + <span class="kw-2">*</span>x = Wrapping(x.<span class="number">0</span>.to_le()); + } + } + <span class="prelude-val">Ok</span>(()) + } + } + }; + (<span class="macro-nonterminal">$t</span>:ty, $(<span class="macro-nonterminal">$tt</span>:ty,)<span class="kw-2">*</span>) => { + <span class="macro">impl_fill!</span>(<span class="macro-nonterminal">$t</span>); + <span class="comment">// TODO: this could replace above impl once Rust #32463 is fixed + // impl_fill!(Wrapping<$t>); + </span><span class="macro">impl_fill!</span>($(<span class="macro-nonterminal">$tt</span>,)<span class="kw-2">*</span>); + } +} + +<span class="macro">impl_fill!</span>(u16, u32, u64, usize, u128,); +<span class="macro">impl_fill!</span>(i8, i16, i32, i64, isize, i128,); + +<span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">"min_const_gen"</span>)))] +#[cfg(feature = <span class="string">"min_const_gen"</span>)] +</span><span class="kw">impl</span><T, <span class="kw">const </span>N: usize> Fill <span class="kw">for </span>[T; N] +<span class="kw">where </span>[T]: Fill +{ + <span class="kw">fn </span>try_fill<R: Rng + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, rng: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="self">self</span>[..].try_fill(rng) + } +} + +<span class="attribute">#[cfg(not(feature = <span class="string">"min_const_gen"</span>))] +</span><span class="macro">macro_rules! </span>impl_fill_arrays { + (<span class="macro-nonterminal">$n</span>:expr,) => {}; + (<span class="macro-nonterminal">$n</span>:expr, <span class="macro-nonterminal">$N</span>:ident) => { + <span class="kw">impl</span><T> Fill <span class="kw">for </span>[T; <span class="macro-nonterminal">$n</span>] <span class="kw">where </span>[T]: Fill { + <span class="kw">fn </span>try_fill<R: Rng + <span class="question-mark">?</span>Sized>(<span class="kw-2">&mut </span><span class="self">self</span>, rng: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="self">self</span>[..].try_fill(rng) + } + } + }; + (<span class="macro-nonterminal">$n</span>:expr, <span class="macro-nonterminal">$N</span>:ident, $(<span class="macro-nonterminal">$NN</span>:ident,)<span class="kw-2">*</span>) => { + <span class="macro">impl_fill_arrays!</span>(<span class="macro-nonterminal">$n</span>, <span class="macro-nonterminal">$N</span>); + <span class="macro">impl_fill_arrays!</span>(<span class="macro-nonterminal">$n </span>- <span class="number">1</span>, $(<span class="macro-nonterminal">$NN</span>,)<span class="kw-2">*</span>); + }; + (!div <span class="macro-nonterminal">$n</span>:expr,) => {}; + (!div <span class="macro-nonterminal">$n</span>:expr, <span class="macro-nonterminal">$N</span>:ident, $(<span class="macro-nonterminal">$NN</span>:ident,)<span class="kw-2">*</span>) => { + <span class="macro">impl_fill_arrays!</span>(<span class="macro-nonterminal">$n</span>, <span class="macro-nonterminal">$N</span>); + <span class="macro">impl_fill_arrays!</span>(!div <span class="macro-nonterminal">$n </span>/ <span class="number">2</span>, $(<span class="macro-nonterminal">$NN</span>,)<span class="kw-2">*</span>); + }; +} +<span class="attribute">#[cfg(not(feature = <span class="string">"min_const_gen"</span>))] +#[rustfmt::skip] +</span><span class="macro">impl_fill_arrays!</span>(<span class="number">32</span>, N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,N,); +<span class="attribute">#[cfg(not(feature = <span class="string">"min_const_gen"</span>))] +</span><span class="macro">impl_fill_arrays!</span>(!div <span class="number">4096</span>, N,N,N,N,N,N,N,); + +<span class="attribute">#[cfg(test)] +</span><span class="kw">mod </span>test { + <span class="kw">use super</span>::<span class="kw-2">*</span>; + <span class="kw">use </span><span class="kw">crate</span>::test::rng; + <span class="kw">use </span><span class="kw">crate</span>::rngs::mock::StepRng; + <span class="attribute">#[cfg(feature = <span class="string">"alloc"</span>)] </span><span class="kw">use </span>alloc::boxed::Box; + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_fill_bytes_default() { + <span class="kw">let </span><span class="kw-2">mut </span>r = StepRng::new(<span class="number">0x11_22_33_44_55_66_77_88</span>, <span class="number">0</span>); + + <span class="comment">// check every remainder mod 8, both in small and big vectors. + </span><span class="kw">let </span>lengths = [<span class="number">0</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">6</span>, <span class="number">7</span>, <span class="number">80</span>, <span class="number">81</span>, <span class="number">82</span>, <span class="number">83</span>, <span class="number">84</span>, <span class="number">85</span>, <span class="number">86</span>, <span class="number">87</span>]; + <span class="kw">for </span><span class="kw-2">&</span>n <span class="kw">in </span>lengths.iter() { + <span class="kw">let </span><span class="kw-2">mut </span>buffer = [<span class="number">0u8</span>; <span class="number">87</span>]; + <span class="kw">let </span>v = <span class="kw-2">&mut </span>buffer[<span class="number">0</span>..n]; + r.fill_bytes(v); + + <span class="comment">// use this to get nicer error messages. + </span><span class="kw">for </span>(i, <span class="kw-2">&</span>byte) <span class="kw">in </span>v.iter().enumerate() { + <span class="kw">if </span>byte == <span class="number">0 </span>{ + <span class="macro">panic!</span>(<span class="string">"byte {} of {} is zero"</span>, i, n) + } + } + } + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_fill() { + <span class="kw">let </span>x = <span class="number">9041086907909331047</span>; <span class="comment">// a random u64 + </span><span class="kw">let </span><span class="kw-2">mut </span>rng = StepRng::new(x, <span class="number">0</span>); + + <span class="comment">// Convert to byte sequence and back to u64; byte-swap twice if BE. + </span><span class="kw">let </span><span class="kw-2">mut </span>array = [<span class="number">0u64</span>; <span class="number">2</span>]; + rng.fill(<span class="kw-2">&mut </span>array[..]); + <span class="macro">assert_eq!</span>(array, [x, x]); + <span class="macro">assert_eq!</span>(rng.next_u64(), x); + + <span class="comment">// Convert to bytes then u32 in LE order + </span><span class="kw">let </span><span class="kw-2">mut </span>array = [<span class="number">0u32</span>; <span class="number">2</span>]; + rng.fill(<span class="kw-2">&mut </span>array[..]); + <span class="macro">assert_eq!</span>(array, [x <span class="kw">as </span>u32, (x >> <span class="number">32</span>) <span class="kw">as </span>u32]); + <span class="macro">assert_eq!</span>(rng.next_u32(), x <span class="kw">as </span>u32); + + <span class="comment">// Check equivalence using wrapped arrays + </span><span class="kw">let </span><span class="kw-2">mut </span>warray = [Wrapping(<span class="number">0u32</span>); <span class="number">2</span>]; + rng.fill(<span class="kw-2">&mut </span>warray[..]); + <span class="macro">assert_eq!</span>(array[<span class="number">0</span>], warray[<span class="number">0</span>].<span class="number">0</span>); + <span class="macro">assert_eq!</span>(array[<span class="number">1</span>], warray[<span class="number">1</span>].<span class="number">0</span>); + + <span class="comment">// Check equivalence for generated floats + </span><span class="kw">let </span><span class="kw-2">mut </span>array = [<span class="number">0f32</span>; <span class="number">2</span>]; + rng.fill(<span class="kw-2">&mut </span>array); + <span class="kw">let </span>gen: [f32; <span class="number">2</span>] = rng.gen(); + <span class="macro">assert_eq!</span>(array, gen); + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_fill_empty() { + <span class="kw">let </span><span class="kw-2">mut </span>array = [<span class="number">0u32</span>; <span class="number">0</span>]; + <span class="kw">let </span><span class="kw-2">mut </span>rng = StepRng::new(<span class="number">0</span>, <span class="number">1</span>); + rng.fill(<span class="kw-2">&mut </span>array); + rng.fill(<span class="kw-2">&mut </span>array[..]); + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_gen_range_int() { + <span class="kw">let </span><span class="kw-2">mut </span>r = rng(<span class="number">101</span>); + <span class="kw">for _ in </span><span class="number">0</span>..<span class="number">1000 </span>{ + <span class="kw">let </span>a = r.gen_range(-<span class="number">4711</span>..<span class="number">17</span>); + <span class="macro">assert!</span>((-<span class="number">4711</span>..<span class="number">17</span>).contains(<span class="kw-2">&</span>a)); + <span class="kw">let </span>a: i8 = r.gen_range(-<span class="number">3</span>..<span class="number">42</span>); + <span class="macro">assert!</span>((-<span class="number">3</span>..<span class="number">42</span>).contains(<span class="kw-2">&</span>a)); + <span class="kw">let </span>a: u16 = r.gen_range(<span class="number">10</span>..<span class="number">99</span>); + <span class="macro">assert!</span>((<span class="number">10</span>..<span class="number">99</span>).contains(<span class="kw-2">&</span>a)); + <span class="kw">let </span>a: i32 = r.gen_range(-<span class="number">100</span>..<span class="number">2000</span>); + <span class="macro">assert!</span>((-<span class="number">100</span>..<span class="number">2000</span>).contains(<span class="kw-2">&</span>a)); + <span class="kw">let </span>a: u32 = r.gen_range(<span class="number">12</span>..=<span class="number">24</span>); + <span class="macro">assert!</span>((<span class="number">12</span>..=<span class="number">24</span>).contains(<span class="kw-2">&</span>a)); + + <span class="macro">assert_eq!</span>(r.gen_range(<span class="number">0u32</span>..<span class="number">1</span>), <span class="number">0u32</span>); + <span class="macro">assert_eq!</span>(r.gen_range(-<span class="number">12i64</span>..-<span class="number">11</span>), -<span class="number">12i64</span>); + <span class="macro">assert_eq!</span>(r.gen_range(<span class="number">3_000_000</span>..<span class="number">3_000_001</span>), <span class="number">3_000_000</span>); + } + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_gen_range_float() { + <span class="kw">let </span><span class="kw-2">mut </span>r = rng(<span class="number">101</span>); + <span class="kw">for _ in </span><span class="number">0</span>..<span class="number">1000 </span>{ + <span class="kw">let </span>a = r.gen_range(-<span class="number">4.5</span>..<span class="number">1.7</span>); + <span class="macro">assert!</span>((-<span class="number">4.5</span>..<span class="number">1.7</span>).contains(<span class="kw-2">&</span>a)); + <span class="kw">let </span>a = r.gen_range(-<span class="number">1.1</span>..=-<span class="number">0.3</span>); + <span class="macro">assert!</span>((-<span class="number">1.1</span>..=-<span class="number">0.3</span>).contains(<span class="kw-2">&</span>a)); + + <span class="macro">assert_eq!</span>(r.gen_range(<span class="number">0.0f32</span>..=<span class="number">0.0</span>), <span class="number">0.</span>); + <span class="macro">assert_eq!</span>(r.gen_range(-<span class="number">11.0</span>..=-<span class="number">11.0</span>), -<span class="number">11.</span>); + <span class="macro">assert_eq!</span>(r.gen_range(<span class="number">3_000_000.0</span>..=<span class="number">3_000_000.0</span>), <span class="number">3_000_000.</span>); + } + } + + <span class="attribute">#[test] + #[should_panic] + </span><span class="kw">fn </span>test_gen_range_panic_int() { + <span class="attribute">#![allow(clippy::reversed_empty_ranges)] + </span><span class="kw">let </span><span class="kw-2">mut </span>r = rng(<span class="number">102</span>); + r.gen_range(<span class="number">5</span>..-<span class="number">2</span>); + } + + <span class="attribute">#[test] + #[should_panic] + </span><span class="kw">fn </span>test_gen_range_panic_usize() { + <span class="attribute">#![allow(clippy::reversed_empty_ranges)] + </span><span class="kw">let </span><span class="kw-2">mut </span>r = rng(<span class="number">103</span>); + r.gen_range(<span class="number">5</span>..<span class="number">2</span>); + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_gen_bool() { + <span class="attribute">#![allow(clippy::bool_assert_comparison)] + + </span><span class="kw">let </span><span class="kw-2">mut </span>r = rng(<span class="number">105</span>); + <span class="kw">for _ in </span><span class="number">0</span>..<span class="number">5 </span>{ + <span class="macro">assert_eq!</span>(r.gen_bool(<span class="number">0.0</span>), <span class="bool-val">false</span>); + <span class="macro">assert_eq!</span>(r.gen_bool(<span class="number">1.0</span>), <span class="bool-val">true</span>); + } + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_rng_trait_object() { + <span class="kw">use </span><span class="kw">crate</span>::distributions::{Distribution, Standard}; + <span class="kw">let </span><span class="kw-2">mut </span>rng = rng(<span class="number">109</span>); + <span class="kw">let </span><span class="kw-2">mut </span>r = <span class="kw-2">&mut </span>rng <span class="kw">as </span><span class="kw-2">&mut </span><span class="kw">dyn </span>RngCore; + r.next_u32(); + r.gen::<i32>(); + <span class="macro">assert_eq!</span>(r.gen_range(<span class="number">0</span>..<span class="number">1</span>), <span class="number">0</span>); + <span class="kw">let </span>_c: u8 = Standard.sample(<span class="kw-2">&mut </span>r); + } + + <span class="attribute">#[test] + #[cfg(feature = <span class="string">"alloc"</span>)] + </span><span class="kw">fn </span>test_rng_boxed_trait() { + <span class="kw">use </span><span class="kw">crate</span>::distributions::{Distribution, Standard}; + <span class="kw">let </span>rng = rng(<span class="number">110</span>); + <span class="kw">let </span><span class="kw-2">mut </span>r = Box::new(rng) <span class="kw">as </span>Box<<span class="kw">dyn </span>RngCore>; + r.next_u32(); + r.gen::<i32>(); + <span class="macro">assert_eq!</span>(r.gen_range(<span class="number">0</span>..<span class="number">1</span>), <span class="number">0</span>); + <span class="kw">let </span>_c: u8 = Standard.sample(<span class="kw-2">&mut </span>r); + } + + <span class="attribute">#[test] + #[cfg_attr(miri, ignore)] </span><span class="comment">// Miri is too slow + </span><span class="kw">fn </span>test_gen_ratio_average() { + <span class="kw">const </span>NUM: u32 = <span class="number">3</span>; + <span class="kw">const </span>DENOM: u32 = <span class="number">10</span>; + <span class="kw">const </span>N: u32 = <span class="number">100_000</span>; + + <span class="kw">let </span><span class="kw-2">mut </span>sum: u32 = <span class="number">0</span>; + <span class="kw">let </span><span class="kw-2">mut </span>rng = rng(<span class="number">111</span>); + <span class="kw">for _ in </span><span class="number">0</span>..N { + <span class="kw">if </span>rng.gen_ratio(NUM, DENOM) { + sum += <span class="number">1</span>; + } + } + <span class="comment">// Have Binomial(N, NUM/DENOM) distribution + </span><span class="kw">let </span>expected = (NUM * N) / DENOM; <span class="comment">// exact integer + </span><span class="macro">assert!</span>(((sum - expected) <span class="kw">as </span>i32).abs() < <span class="number">500</span>); + } +} +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
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