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uuid

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import native from './native.js'; import rng from './rng.js'; import { unsafeStringify } from './stringify.js'; function v4(options, buf, offset) { if (native.randomUUID && !buf && !options) { return native.randomUUID(); } options = options || {}; const rnds = options.random ?? options.rng?.() ?? rng(); if (rnds.length < 16) { throw new Error('Random bytes length must be >= 16'); } rnds[6] = (rnds[6] & 0x0f) | 0x40; rnds[8] = (rnds[8] & 0x3f) | 0x80; if (buf) { offset = offset || 0; if (offset < 0 || offset + 16 > buf.length) { throw new RangeError(`UUID byte range ${offset}:${offset + 15} is out of buffer bounds`); } for (let i = 0; i < 16; ++i) { buf[offset + i] = rnds[i]; } return buf; } return unsafeStringify(rnds); } export default v4;