utf8.d.ts 3.9 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596
  1. import type { BytesLike } from "./index.js";
  2. /**
  3. * The stanard normalization forms.
  4. */
  5. export type UnicodeNormalizationForm = "NFC" | "NFD" | "NFKC" | "NFKD";
  6. /**
  7. * When using the UTF-8 error API the following errors can be intercepted
  8. * and processed as the %%reason%% passed to the [[Utf8ErrorFunc]].
  9. *
  10. * **``"UNEXPECTED_CONTINUE"``** - a continuation byte was present where there
  11. * was nothing to continue.
  12. *
  13. * **``"BAD_PREFIX"``** - an invalid (non-continuation) byte to start a
  14. * UTF-8 codepoint was found.
  15. *
  16. * **``"OVERRUN"``** - the string is too short to process the expected
  17. * codepoint length.
  18. *
  19. * **``"MISSING_CONTINUE"``** - a missing continuation byte was expected but
  20. * not found. The %%offset%% indicates the index the continuation byte
  21. * was expected at.
  22. *
  23. * **``"OUT_OF_RANGE"``** - the computed code point is outside the range
  24. * for UTF-8. The %%badCodepoint%% indicates the computed codepoint, which was
  25. * outside the valid UTF-8 range.
  26. *
  27. * **``"UTF16_SURROGATE"``** - the UTF-8 strings contained a UTF-16 surrogate
  28. * pair. The %%badCodepoint%% is the computed codepoint, which was inside the
  29. * UTF-16 surrogate range.
  30. *
  31. * **``"OVERLONG"``** - the string is an overlong representation. The
  32. * %%badCodepoint%% indicates the computed codepoint, which has already
  33. * been bounds checked.
  34. *
  35. *
  36. * @returns string
  37. */
  38. export type Utf8ErrorReason = "UNEXPECTED_CONTINUE" | "BAD_PREFIX" | "OVERRUN" | "MISSING_CONTINUE" | "OUT_OF_RANGE" | "UTF16_SURROGATE" | "OVERLONG";
  39. /**
  40. * A callback that can be used with [[toUtf8String]] to analysis or
  41. * recovery from invalid UTF-8 data.
  42. *
  43. * Parsing UTF-8 data is done through a simple Finite-State Machine (FSM)
  44. * which calls the ``Utf8ErrorFunc`` if a fault is detected.
  45. *
  46. * The %%reason%% indicates where in the FSM execution the fault
  47. * occurred and the %%offset%% indicates where the input failed.
  48. *
  49. * The %%bytes%% represents the raw UTF-8 data that was provided and
  50. * %%output%% is the current array of UTF-8 code-points, which may
  51. * be updated by the ``Utf8ErrorFunc``.
  52. *
  53. * The value of the %%badCodepoint%% depends on the %%reason%%. See
  54. * [[Utf8ErrorReason]] for details.
  55. *
  56. * The function should return the number of bytes that should be skipped
  57. * when control resumes to the FSM.
  58. */
  59. export type Utf8ErrorFunc = (reason: Utf8ErrorReason, offset: number, bytes: Uint8Array, output: Array<number>, badCodepoint?: number) => number;
  60. /**
  61. * A handful of popular, built-in UTF-8 error handling strategies.
  62. *
  63. * **``"error"``** - throws on ANY illegal UTF-8 sequence or
  64. * non-canonical (overlong) codepoints (this is the default)
  65. *
  66. * **``"ignore"``** - silently drops any illegal UTF-8 sequence
  67. * and accepts non-canonical (overlong) codepoints
  68. *
  69. * **``"replace"``** - replace any illegal UTF-8 sequence with the
  70. * UTF-8 replacement character (i.e. ``"\\ufffd"``) and accepts
  71. * non-canonical (overlong) codepoints
  72. *
  73. * @returns: Record<"error" | "ignore" | "replace", Utf8ErrorFunc>
  74. */
  75. export declare const Utf8ErrorFuncs: Readonly<Record<"error" | "ignore" | "replace", Utf8ErrorFunc>>;
  76. /**
  77. * Returns the UTF-8 byte representation of %%str%%.
  78. *
  79. * If %%form%% is specified, the string is normalized.
  80. */
  81. export declare function toUtf8Bytes(str: string, form?: UnicodeNormalizationForm): Uint8Array;
  82. /**
  83. * Returns the string represented by the UTF-8 data %%bytes%%.
  84. *
  85. * When %%onError%% function is specified, it is called on UTF-8
  86. * errors allowing recovery using the [[Utf8ErrorFunc]] API.
  87. * (default: [error](Utf8ErrorFuncs))
  88. */
  89. export declare function toUtf8String(bytes: BytesLike, onError?: Utf8ErrorFunc): string;
  90. /**
  91. * Returns the UTF-8 code-points for %%str%%.
  92. *
  93. * If %%form%% is specified, the string is normalized.
  94. */
  95. export declare function toUtf8CodePoints(str: string, form?: UnicodeNormalizationForm): Array<number>;
  96. //# sourceMappingURL=utf8.d.ts.map