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- let random = async bytes => crypto.getRandomValues(new Uint8Array(bytes))
- let customAlphabet = (alphabet, defaultSize = 21) => {
- let mask = (2 << (Math.log(alphabet.length - 1) / Math.LN2)) - 1
- let step = -~((1.6 * mask * defaultSize) / alphabet.length)
- return async (size = defaultSize) => {
- let id = ''
- while (true) {
- let bytes = crypto.getRandomValues(new Uint8Array(step))
- let i = step
- while (i--) {
- id += alphabet[bytes[i] & mask] || ''
- if (id.length === size) return id
- }
- }
- }
- }
- let nanoid = async (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, random }
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