14 lines
540 B
TypeScript
14 lines
540 B
TypeScript
/** Fast deterministic hash to shorten long strings */
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export function shortHash(str: string): string {
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let h1 = 0xdeadbeef;
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let h2 = 0x41c6ce57;
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for (let i = 0; i < str.length; i++) {
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const ch = str.charCodeAt(i);
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h1 = Math.imul(h1 ^ ch, 2654435761);
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h2 = Math.imul(h2 ^ ch, 1597334677);
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}
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h1 = Math.imul(h1 ^ (h1 >>> 16), 2246822507) ^ Math.imul(h2 ^ (h2 >>> 13), 3266489909);
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h2 = Math.imul(h2 ^ (h2 >>> 16), 2246822507) ^ Math.imul(h1 ^ (h1 >>> 13), 3266489909);
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return (h2 >>> 0).toString(36) + (h1 >>> 0).toString(36);
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}
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