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- let { urlAlphabet } = require('./url-alphabet/index.cjs')
- let random = bytes => crypto.getRandomValues(new Uint8Array(bytes))
- let customRandom = (alphabet, defaultSize, getRandom) => {
- let mask = (2 << (Math.log(alphabet.length - 1) / Math.LN2)) - 1
- let step = -~((1.6 * mask * defaultSize) / alphabet.length)
- return (size = defaultSize) => {
- let id = ''
- while (true) {
- let bytes = getRandom(step)
- let j = step
- while (j--) {
- id += alphabet[bytes[j] & mask] || ''
- if (id.length === size) return id
- }
- }
- }
- }
- let customAlphabet = (alphabet, size = 21) =>
- customRandom(alphabet, size, random)
- let nanoid = (size = 21) => {
- let id = ''
- let bytes = crypto.getRandomValues(new Uint8Array(size))
- while (size--) {
- let byte = bytes[size] & 63
- if (byte < 36) {
- id += byte.toString(36)
- } else if (byte < 62) {
- id += (byte - 26).toString(36).toUpperCase()
- } else if (byte < 63) {
- id += '_'
- } else {
- id += '-'
- }
- }
- return id
- }
- module.exports = { nanoid, customAlphabet, customRandom, urlAlphabet, random }
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