7820380e
 “wangming”
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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
}
export { nanoid, customAlphabet, random }
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