index.browser.js 1.1 KB

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  1. import { urlAlphabet } from './url-alphabet/index.js'
  2. let random = bytes => crypto.getRandomValues(new Uint8Array(bytes))
  3. let customRandom = (alphabet, defaultSize, getRandom) => {
  4. let mask = (2 << (Math.log(alphabet.length - 1) / Math.LN2)) - 1
  5. let step = -~((1.6 * mask * defaultSize) / alphabet.length)
  6. return (size = defaultSize) => {
  7. if (size <= 0) return ''
  8. let id = ''
  9. while (true) {
  10. let bytes = getRandom(step)
  11. let j = step | 0
  12. while (j--) {
  13. id += alphabet[bytes[j] & mask] || ''
  14. if (id.length === size) return id
  15. }
  16. }
  17. }
  18. }
  19. let customAlphabet = (alphabet, size = 21) =>
  20. customRandom(alphabet, size, random)
  21. let nanoid = (size = 21) =>
  22. crypto.getRandomValues(new Uint8Array(size)).reduce((id, byte) => {
  23. byte &= 63
  24. if (byte < 36) {
  25. id += byte.toString(36)
  26. } else if (byte < 62) {
  27. id += (byte - 26).toString(36).toUpperCase()
  28. } else if (byte > 62) {
  29. id += '-'
  30. } else {
  31. id += '_'
  32. }
  33. return id
  34. }, '')
  35. export { nanoid, customAlphabet, customRandom, urlAlphabet, random }