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<p class='location'>Struct JitterRng</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.new">new</a><a href="#method.new_with_timer">new_with_timer</a><a href="#method.set_rounds">set_rounds</a><a href="#method.test_timer">test_timer</a><a href="#method.timer_stats">timer_stats</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Debug">Debug</a><a href="#impl-Rng">Rng</a></div></div><p class='location'><a href='../index.html'>rand</a>::<wbr><a href='index.html'>jitter</a></p><script>window.sidebarCurrent = {name: 'JitterRng', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div>
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<h1 class='fqn'><span class='in-band'>Struct <a href='../index.html'>rand</a>::<wbr><a href='index.html'>jitter</a>::<wbr><a class="struct" href=''>JitterRng</a></span><span class='out-of-band'><span id='render-detail'>
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<a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
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[<span class='inner'>−</span>]
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</a>
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</span><a class='srclink' href='../../src/rand/jitter.rs.html#51-66' title='goto source code'>[src]</a></span></h1>
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<pre class='rust struct'>pub struct JitterRng { /* fields omitted */ }</pre><div class='docblock'><p>A true random number generator based on jitter in the CPU execution time,
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and jitter in memory access time.</p>
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<p>This is a true random number generator, as opposed to pseudo-random
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generators. Random numbers generated by <code>JitterRng</code> can be seen as fresh
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entropy. A consequence is that is orders of magnitude slower than <code>OsRng</code>
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and PRNGs (about 10^3 .. 10^6 slower).</p>
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<p>There are very few situations where using this RNG is appropriate. Only very
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few applications require true entropy. A normal PRNG can be statistically
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indistinguishable, and a cryptographic PRNG should also be as impossible to
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predict.</p>
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<p>Use of <code>JitterRng</code> is recommended for initializing cryptographic PRNGs when
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<code>OsRng</code> is not available.</p>
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<p>This implementation is based on
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<a href="http://www.chronox.de/jent.html">Jitterentropy</a> version 2.1.0.</p>
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</div>
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<h2 id='methods' class='small-section-header'>
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Methods<a href='#methods' class='anchor'></a>
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</h2>
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<h3 id='impl' class='impl'><span class='in-band'><code>impl <a class="struct" href="../../rand/jitter/struct.JitterRng.html" title="struct rand::jitter::JitterRng">JitterRng</a></code><a href='#impl' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#122-663' title='goto source code'>[src]</a></span></h3>
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<div class='impl-items'><h4 id='method.new' class="method"><span id='new.v' class='invisible'><code>pub fn <a href='#method.new' class='fnname'>new</a>() -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="struct" href="../../rand/jitter/struct.JitterRng.html" title="struct rand::jitter::JitterRng">JitterRng</a>, <a class="enum" href="../../rand/jitter/enum.TimerError.html" title="enum rand::jitter::TimerError">TimerError</a>></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#130-141' title='goto source code'>[src]</a></span></h4>
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<div class='docblock'><p>Create a new <code>JitterRng</code>.
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Makes use of <code>std::time</code> for a timer.</p>
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<p>During initialization CPU execution timing jitter is measured a few
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hundred times. If this does not pass basic quality tests, an error is
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returned. The test result is cached to make subsequent calls faster.</p>
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</div><h4 id='method.new_with_timer' class="method"><span id='new_with_timer.v' class='invisible'><code>pub fn <a href='#method.new_with_timer' class='fnname'>new_with_timer</a>(timer: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.fn.html">fn</a>() -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a>) -> <a class="struct" href="../../rand/jitter/struct.JitterRng.html" title="struct rand::jitter::JitterRng">JitterRng</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#152-177' title='goto source code'>[src]</a></span></h4>
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<div class='docblock'><p>Create a new <code>JitterRng</code>.
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A custom timer can be supplied, making it possible to use <code>JitterRng</code> in
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<code>no_std</code> environments.</p>
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<p>The timer must have nanosecond precision.</p>
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<p>This method is more low-level than <code>new()</code>. It is the responsibility of
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the caller to run <code>test_timer</code> before using any numbers generated with
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<code>JitterRng</code>, and optionally call <code>set_rounds()</code>.</p>
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</div><h4 id='method.set_rounds' class="method"><span id='set_rounds.v' class='invisible'><code>pub fn <a href='#method.set_rounds' class='fnname'>set_rounds</a>(&mut self, rounds: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u32.html">u32</a>)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#187-190' title='goto source code'>[src]</a></span></h4>
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<div class='docblock'><p>Configures how many rounds are used to generate each 64-bit value.
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This must be greater than zero, and has a big impact on performance
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and output quality.</p>
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<p><code>new_with_timer</code> conservatively uses 64 rounds, but often less rounds
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can be used. The <code>test_timer()</code> function returns the minimum number of
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rounds required for full strength (platform dependent), so one may use
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<code>rng.set_rounds(rng.test_timer()?);</code> or cache the value.</p>
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</div><h4 id='method.test_timer' class="method"><span id='test_timer.v' class='invisible'><code>pub fn <a href='#method.test_timer' class='fnname'>test_timer</a>(&mut self) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u32.html">u32</a>, <a class="enum" href="../../rand/jitter/enum.TimerError.html" title="enum rand::jitter::TimerError">TimerError</a>></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#439-562' title='goto source code'>[src]</a></span></h4>
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<div class='docblock'><p>Basic quality tests on the timer, by measuring CPU timing jitter a few
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hundred times.</p>
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<p>If succesful, this will return the estimated number of rounds necessary
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to collect 64 bits of entropy. Otherwise a <code>TimerError</code> with the cause
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of the failure will be returned.</p>
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</div><h4 id='method.timer_stats' class="method"><span id='timer_stats.v' class='invisible'><code>pub fn <a href='#method.timer_stats' class='fnname'>timer_stats</a>(&mut self, var_rounds: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a>) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.i64.html">i64</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#656-662' title='goto source code'>[src]</a></span></h4>
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<div class='docblock'><p>Statistical test: return the timer delta of one normal run of the
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<code>JitterEntropy</code> entropy collector.</p>
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<p>Setting <code>var_rounds</code> to <code>true</code> will execute the memory access and the
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CPU jitter noice sources a variable amount of times (just like a real
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<code>JitterEntropy</code> round).</p>
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<p>Setting <code>var_rounds</code> to <code>false</code> will execute the noice sources the
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minimal number of times. This can be used to measure the minimum amount
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of entropy one round of entropy collector can collect in the worst case.</p>
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<h1 id="example" class="section-header"><a href="#example">Example</a></h1>
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<p>Use <code>timer_stats</code> to run the [NIST SP 800-90B Entropy Estimation Suite]
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(https://github.com/usnistgov/SP800-90B_EntropyAssessment).</p>
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<p>This is the recommended way to test the quality of <code>JitterRng</code>. It
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should be run before using the RNG on untested hardware, after changes
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that could effect how the code is optimised, and after major compiler
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compiler changes, like a new LLVM version.</p>
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<p>First generate two files <code>jitter_rng_var.bin</code> and <code>jitter_rng_var.min</code>.</p>
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<p>Execute <code>python noniid_main.py -v jitter_rng_var.bin 8</code>, and validate it
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with <code>restart.py -v jitter_rng_var.bin 8 <min-entropy></code>.
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This number is the expected amount of entropy that is at least available
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for each round of the entropy collector. This number should be greater
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than the amount estimated with <code>64 / test_timer()</code>.</p>
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<p>Execute <code>python noniid_main.py -v -u 4 jitter_rng_var.bin 4</code>, and
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validate it with <code>restart.py -v -u 4 jitter_rng_var.bin 4 <min-entropy></code>.
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This number is the expected amount of entropy that is available in the
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last 4 bits of the timer delta after running noice sources. Note that
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a value of 3.70 is the minimum estimated entropy for true randomness.</p>
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<p>Execute <code>python noniid_main.py -v -u 4 jitter_rng_var.bin 4</code>, and
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validate it with <code>restart.py -v -u 4 jitter_rng_var.bin 4 <min-entropy></code>.
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This number is the expected amount of entropy that is available to the
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entropy collecter if both noice sources only run their minimal number of
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times. This measures the absolute worst-case, and gives a lower bound
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for the available entropy.</p>
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<pre class="rust rust-example-rendered">
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<span class="kw">use</span> <span class="ident">rand</span>::<span class="ident">JitterRng</span>;
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<span class="kw">fn</span> <span class="ident">get_nstime</span>() <span class="op">-></span> <span class="ident">u64</span> {
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<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">time</span>::{<span class="ident">SystemTime</span>, <span class="ident">UNIX_EPOCH</span>};
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<span class="kw">let</span> <span class="ident">dur</span> <span class="op">=</span> <span class="ident">SystemTime</span>::<span class="ident">now</span>().<span class="ident">duration_since</span>(<span class="ident">UNIX_EPOCH</span>).<span class="ident">unwrap</span>();
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<span class="comment">// The correct way to calculate the current time is</span>
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<span class="comment">// `dur.as_secs() * 1_000_000_000 + dur.subsec_nanos() as u64`</span>
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<span class="comment">// But this is faster, and the difference in terms of entropy is</span>
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<span class="comment">// negligible (log2(10^9) == 29.9).</span>
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<span class="ident">dur</span>.<span class="ident">as_secs</span>() <span class="op"><<</span> <span class="number">30</span> <span class="op">|</span> <span class="ident">dur</span>.<span class="ident">subsec_nanos</span>() <span class="kw">as</span> <span class="ident">u64</span>
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}
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<span class="comment">// Do not initialize with `JitterRng::new`, but with `new_with_timer`.</span>
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<span class="comment">// 'new' always runst `test_timer`, and can therefore fail to</span>
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<span class="comment">// initialize. We want to be able to get the statistics even when the</span>
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<span class="comment">// timer test fails.</span>
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<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">rng</span> <span class="op">=</span> <span class="ident">JitterRng</span>::<span class="ident">new_with_timer</span>(<span class="ident">get_nstime</span>);
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<span class="comment">// 1_000_000 results are required for the NIST SP 800-90B Entropy</span>
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<span class="comment">// Estimation Suite</span>
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<span class="comment">// FIXME: this number is smaller here, otherwise the Doc-test is too slow</span>
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<span class="kw">const</span> <span class="ident">ROUNDS</span>: <span class="ident">usize</span> <span class="op">=</span> <span class="number">10_000</span>;
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<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">deltas_variable</span>: <span class="ident">Vec</span><span class="op"><</span><span class="ident">u8</span><span class="op">></span> <span class="op">=</span> <span class="ident">Vec</span>::<span class="ident">with_capacity</span>(<span class="ident">ROUNDS</span>);
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<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">deltas_minimal</span>: <span class="ident">Vec</span><span class="op"><</span><span class="ident">u8</span><span class="op">></span> <span class="op">=</span> <span class="ident">Vec</span>::<span class="ident">with_capacity</span>(<span class="ident">ROUNDS</span>);
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<span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="ident">ROUNDS</span> {
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<span class="ident">deltas_variable</span>.<span class="ident">push</span>(<span class="ident">rng</span>.<span class="ident">timer_stats</span>(<span class="bool-val">true</span>) <span class="kw">as</span> <span class="ident">u8</span>);
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<span class="ident">deltas_minimal</span>.<span class="ident">push</span>(<span class="ident">rng</span>.<span class="ident">timer_stats</span>(<span class="bool-val">false</span>) <span class="kw">as</span> <span class="ident">u8</span>);
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}
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<span class="comment">// Write out after the statistics collection loop, to not disturb the</span>
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<span class="comment">// test results.</span>
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<span class="ident">File</span>::<span class="ident">create</span>(<span class="string">"jitter_rng_var.bin"</span>)<span class="question-mark">?</span>.<span class="ident">write</span>(<span class="kw-2">&</span><span class="ident">deltas_variable</span>)<span class="question-mark">?</span>;
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<span class="ident">File</span>::<span class="ident">create</span>(<span class="string">"jitter_rng_min.bin"</span>)<span class="question-mark">?</span>.<span class="ident">write</span>(<span class="kw-2">&</span><span class="ident">deltas_minimal</span>)<span class="question-mark">?</span>;</pre>
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</div></div>
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<h2 id='implementations' class='small-section-header'>
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Trait Implementations<a href='#implementations' class='anchor'></a>
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</h2>
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<h3 id='impl-Debug' class='impl'><span class='in-band'><code>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="../../rand/jitter/struct.JitterRng.html" title="struct rand::jitter::JitterRng">JitterRng</a></code><a href='#impl-Debug' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#69-73' title='goto source code'>[src]</a></span></h3>
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<div class='impl-items'><h4 id='method.fmt' class="method"><span id='fmt.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&self, f: &mut <a class="struct" href="https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>) -> <a class="type" href="https://doc.rust-lang.org/nightly/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#70-72' title='goto source code'>[src]</a></span></h4>
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<div class='docblock'><p>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
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</div></div><h3 id='impl-Rng' class='impl'><span class='in-band'><code>impl <a class="trait" href="../../rand/trait.Rng.html" title="trait rand::Rng">Rng</a> for <a class="struct" href="../../rand/jitter/struct.JitterRng.html" title="struct rand::jitter::JitterRng">JitterRng</a></code><a href='#impl-Rng' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#717-751' title='goto source code'>[src]</a></span></h3>
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<div class='impl-items'><h4 id='method.next_u32' class="method"><span id='next_u32.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#tymethod.next_u32' class='fnname'>next_u32</a>(&mut self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u32.html">u32</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#718-727' title='goto source code'>[src]</a></span></h4>
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<div class='docblock'><p>Return the next random u32. <a href="../../rand/trait.Rng.html#tymethod.next_u32">Read more</a></p>
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</div><h4 id='method.next_u64' class="method"><span id='next_u64.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.next_u64' class='fnname'>next_u64</a>(&mut self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u64.html">u64</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#729-731' title='goto source code'>[src]</a></span></h4>
|
|||
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<div class='docblock'><p>Return the next random u64. <a href="../../rand/trait.Rng.html#method.next_u64">Read more</a></p>
|
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|
</div><h4 id='method.fill_bytes' class="method"><span id='fill_bytes.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.fill_bytes' class='fnname'>fill_bytes</a>(&mut self, dest: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">&mut [</a><a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u8.html">u8</a><a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">]</a>)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/jitter.rs.html#733-750' title='goto source code'>[src]</a></span></h4>
|
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<div class='docblock'><p>Fill <code>dest</code> with random data. <a href="../../rand/trait.Rng.html#method.fill_bytes">Read more</a></p>
|
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|
</div><h4 id='method.next_f32' class="method"><span id='next_f32.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.next_f32' class='fnname'>next_f32</a>(&mut self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.f32.html">f32</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#383-389' title='goto source code'>[src]</a></span></h4>
|
|||
|
<div class='docblock'><p>Return the next random f32 selected from the half-open interval <code>[0, 1)</code>. <a href="../../rand/trait.Rng.html#method.next_f32">Read more</a></p>
|
|||
|
</div><h4 id='method.next_f64' class="method"><span id='next_f64.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.next_f64' class='fnname'>next_f64</a>(&mut self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.f64.html">f64</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#401-407' title='goto source code'>[src]</a></span></h4>
|
|||
|
<div class='docblock'><p>Return the next random f64 selected from the half-open interval <code>[0, 1)</code>. <a href="../../rand/trait.Rng.html#method.next_f64">Read more</a></p>
|
|||
|
</div><h4 id='method.gen' class="method"><span id='gen.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.gen' class='fnname'>gen</a><T: <a class="trait" href="../../rand/trait.Rand.html" title="trait rand::Rand">Rand</a>>(&mut self) -> T <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#473-475' title='goto source code'>[src]</a></span></h4>
|
|||
|
<div class='docblock'><p>Return a random value of a <code>Rand</code> type. <a href="../../rand/trait.Rng.html#method.gen">Read more</a></p>
|
|||
|
</div><h4 id='method.gen_iter' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="struct" href="../../rand/struct.Generator.html" title="struct rand::Generator">Generator</a><'a, T, R></span></div><div class="content hidden"><h3 class="important">Important traits for <a class="struct" href="../../rand/struct.Generator.html" title="struct rand::Generator">Generator</a><'a, T, R></h3><code class="content"><span class="where fmt-newline">impl<'a, T: <a class="trait" href="../../rand/trait.Rand.html" title="trait rand::Rand">Rand</a>, R: <a class="trait" href="../../rand/trait.Rng.html" title="trait rand::Rng">Rng</a>> <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/iterator/trait.Iterator.html" title="trait core::iter::iterator::Iterator">Iterator</a> for <a class="struct" href="../../rand/struct.Generator.html" title="struct rand::Generator">Generator</a><'a, T, R></span><span class="where fmt-newline"> type <a href='https://doc.rust-lang.org/nightly/core/iter/iterator/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = T;</span></code></div></div><span id='gen_iter.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.gen_iter' class='fnname'>gen_iter</a><'a, T: <a class="trait" href="../../rand/trait.Rand.html" title="trait rand::Rand">Rand</a>>(&'a mut self) -> <a class="struct" href="../../rand/struct.Generator.html" title="struct rand::Generator">Generator</a><'a, T, Self> <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#491-493' title='goto source code'>[src]</a></span></h4>
|
|||
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<div class='docblock'><p>Return an iterator that will yield an infinite number of randomly generated items. <a href="../../rand/trait.Rng.html#method.gen_iter">Read more</a></p>
|
|||
|
</div><h4 id='method.gen_range' class="method"><span id='gen_range.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.gen_range' class='fnname'>gen_range</a><T: <a class="trait" href="https://doc.rust-lang.org/nightly/core/cmp/trait.PartialOrd.html" title="trait core::cmp::PartialOrd">PartialOrd</a> + <a class="trait" href="../../rand/distributions/range/trait.SampleRange.html" title="trait rand::distributions::range::SampleRange">SampleRange</a>>(&mut self, low: T, high: T) -> T <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#518-521' title='goto source code'>[src]</a></span></h4>
|
|||
|
<div class='docblock'><p>Generate a random value in the range [<code>low</code>, <code>high</code>). <a href="../../rand/trait.Rng.html#method.gen_range">Read more</a></p>
|
|||
|
</div><h4 id='method.gen_weighted_bool' class="method"><span id='gen_weighted_bool.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.gen_weighted_bool' class='fnname'>gen_weighted_bool</a>(&mut self, n: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.u32.html">u32</a>) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a> <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#533-535' title='goto source code'>[src]</a></span></h4>
|
|||
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<div class='docblock'><p>Return a bool with a 1 in n chance of true <a href="../../rand/trait.Rng.html#method.gen_weighted_bool">Read more</a></p>
|
|||
|
</div><h4 id='method.gen_ascii_chars' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="struct" href="../../rand/struct.AsciiGenerator.html" title="struct rand::AsciiGenerator">AsciiGenerator</a><'a, R></span></div><div class="content hidden"><h3 class="important">Important traits for <a class="struct" href="../../rand/struct.AsciiGenerator.html" title="struct rand::AsciiGenerator">AsciiGenerator</a><'a, R></h3><code class="content"><span class="where fmt-newline">impl<'a, R: <a class="trait" href="../../rand/trait.Rng.html" title="trait rand::Rng">Rng</a>> <a class="trait" href="https://doc.rust-lang.org/nightly/core/iter/iterator/trait.Iterator.html" title="trait core::iter::iterator::Iterator">Iterator</a> for <a class="struct" href="../../rand/struct.AsciiGenerator.html" title="struct rand::AsciiGenerator">AsciiGenerator</a><'a, R></span><span class="where fmt-newline"> type <a href='https://doc.rust-lang.org/nightly/core/iter/iterator/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.char.html">char</a>;</span></code></div></div><span id='gen_ascii_chars.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.gen_ascii_chars' class='fnname'>gen_ascii_chars</a><'a>(&'a mut self) -> <a class="struct" href="../../rand/struct.AsciiGenerator.html" title="struct rand::AsciiGenerator">AsciiGenerator</a><'a, Self> <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#547-549' title='goto source code'>[src]</a></span></h4>
|
|||
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<div class='docblock'><p>Return an iterator of random characters from the set A-Z,a-z,0-9. <a href="../../rand/trait.Rng.html#method.gen_ascii_chars">Read more</a></p>
|
|||
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</div><h4 id='method.choose' class="method"><span id='choose.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.choose' class='fnname'>choose</a><'a, T>(&mut self, values: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">&'a [T]</a>) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html" title="enum core::option::Option">Option</a><<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&'a </a>T> <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#565-571' title='goto source code'>[src]</a></span></h4>
|
|||
|
<div class='docblock'><p>Return a random element from <code>values</code>. <a href="../../rand/trait.Rng.html#method.choose">Read more</a></p>
|
|||
|
</div><h4 id='method.choose_mut' class="method"><span id='choose_mut.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.choose_mut' class='fnname'>choose_mut</a><'a, T>(&mut self, values: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">&'a mut [T]</a>) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html" title="enum core::option::Option">Option</a><<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&'a mut </a>T> <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#576-583' title='goto source code'>[src]</a></span></h4>
|
|||
|
<div class='docblock'><p>Return a mutable pointer to a random element from <code>values</code>. <a href="../../rand/trait.Rng.html#method.choose_mut">Read more</a></p>
|
|||
|
</div><h4 id='method.shuffle' class="method"><span id='shuffle.v' class='invisible'><code>fn <a href='../../rand/trait.Rng.html#method.shuffle' class='fnname'>shuffle</a><T>(&mut self, values: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.slice.html">&mut [T]</a>) <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/rand/lib.rs.html#602-610' title='goto source code'>[src]</a></span></h4>
|
|||
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<div class='docblock'><p>Shuffle a mutable slice in place. <a href="../../rand/trait.Rng.html#method.shuffle">Read more</a></p>
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