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<meta name="description" content="FNV-1a 64-bit, named explicitly.">
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<div class="crumbs"><a href="api.html">API Reference</a> <span>›</span> <a href="ns-hash.html">Hash</a> <span>›</span> <span class="here">Hash.fnv1a_64</span></div>
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<span class="kind-badge kind-method">method</span>
<h1 id="top">Hash.fnv1a_64</h1>
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<code class="sig">Hash.fnv1a_64(s) -&gt; long</code>
<div class="desc"><p>The 64-bit <a href="https://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function">FNV-1a</a> hash of a string's bytes, returned as a <code>long</code>. It uses the standard 64-bit offset basis <code>0xcbf29ce484222325</code> and prime <code>0x100000001b3</code>: for each byte, XOR it in and multiply by the prime. Its wider output makes accidental collisions vanishingly unlikely for the id and registry use cases games hit. This is the function <a href="hash-of64"><code>Hash.of64</code></a> delegates to; call <code>Hash.fnv1a_64</code> when you want the algorithm pinned by name.</p></div>
<div class="params"><h2>Parameters</h2><div class="param" id="param-s"><code class="pname">s</code><span class="pdesc">the string to hash</span></div></div>
<div class="examples"><h2>Example</h2><pre data-lang="ludic">program Fnv64 {
entry {
print(Hash.fnv1a_64("")) # the empty string -&gt; the 64-bit offset basis
print(Hash.fnv1a_64("grass_tile"))
}
}</pre></div>
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