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mildsunrise/crc32.js

Last active September 23, 2019 11:38
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crc32.js
const table = new Int32Array(256).map((_,n) => [...Array(8)]
.reduce(c => (c>>>1) ^ ((c&1) * 0xEDB88320), n))
const fn = (C, b) => (C>>>8) ^ table[(C^b) & 0xFF]
const crc = (x, seed) => ~x.reduce(fn, ~seed)
// Example:
crc( Buffer.from('Hello') ) === 0xF7D18982
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