it-tools/utils/random.ts

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import {randomBytes} from 'crypto'
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const random = () => randomBytes(4).readUInt32LE(0) / 0x100000000
const randFromArray = (array: any[]) => array[Math.floor(random() * array.length)]
const randIntFromInterval = (min: number, max: number) => Math.floor(random() * (max - min) + min)
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// Durstenfeld shuffle
const shuffleArrayMutate = <T extends unknown>(array: T[]): T[] => {
for (let i = array.length - 1; i > 0; i--) {
const j = Math.floor(Math.random() * (i + 1));
[array[i], array[j]] = [array[j], array[i]];
}
return array
}
const shuffleArray = <T extends unknown>(array: T[]): T[] => shuffleArrayMutate([...array])
const shuffleString = (str: string, delimiter: string = ''): string => shuffleArrayMutate(str.split(delimiter)).join(delimiter)
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export {
randFromArray,
randIntFromInterval,
random,
shuffleArray,
shuffleArrayMutate,
shuffleString
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}