assets/js/bitstring.mjs (1)

255-269: Consider hoisting lookup objects to module/class level.

firstByteMasks (Line 259) and minValueForLength (Line 623) are allocated on every call. Since these are constants, they could be static class fields or module-level constants to avoid repeated allocation.

♻️ Suggested refactor

 export default class Bitstring {
   static `#decoder` = ERTS.utf8Decoder;
   static `#encoder` = new TextEncoder("utf-8");
+  static `#utf8FirstByteMasks` = {2: 0x1f, 3: 0x0f, 4: 0x07};
+  static `#utf8MinCodePointForLength` = {1: 0, 2: 0x80, 3: 0x800, 4: 0x10000};

Then reference $.#utf8FirstByteMasks[length] and $.#utf8MinCodePointForLength[encodingLength] respectively.

Also applies to: 617-633

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@assets/js/bitstring.mjs` around lines 255 - 269, The function
decodeUtf8CodePoint allocates the lookup object firstByteMasks on every call
(and similarly minValueForLength elsewhere), so hoist these constant maps to
module/class scope as static fields to avoid repeated allocation; create
constants (e.g. utf8FirstByteMasks and utf8MinCodePointForLength) at the top of
the module or as private static fields on the BitString class and replace local
usages of firstByteMasks and minValueForLength with references to those
static/module constants (e.g., BitString.#utf8FirstByteMasks[length] or the
module-level utf8FirstByteMasks[length]).

assets/js/erlang/unicode.mjs (1)

271-354: Consider extracting a shared normalization handler parameterized by form.

The characters_to_nfc_binary/1, characters_to_nfd_binary/1, characters_to_nfkc_binary/1, and characters_to_nfkd_binary/1 functions are structurally identical — they differ only in the normalization form string ("NFC", "NFD", "NFKC", "NFKD"). The handleInvalidUtf8, handleConversionError, and validateListRest helpers are duplicated verbatim across all four.

Since this PR already modifies the handleInvalidUtf8 in each variant (switching to Bitstring.getValidUtf8Length), it would be a natural time to extract a shared factory:

♻️ Sketch

const makeNormalizationBinaryFn = (form) => (data) => {
  const validateListRest = (rest) => { /* shared */ };
  const handleConversionError = (tag, prefix, rest) => {
    // ...textPrefix.normalize(form)...
  };
  const handleInvalidUtf8 = (bytes) => {
    // ...validText.normalize(form)...
  };
  // ...main logic identical...
};

"characters_to_nfc_binary/1": makeNormalizationBinaryFn("NFC"),
"characters_to_nfd_binary/1": makeNormalizationBinaryFn("NFD"),
"characters_to_nfkc_binary/1": makeNormalizationBinaryFn("NFKC"),
"characters_to_nfkd_binary/1": makeNormalizationBinaryFn("NFKD"),

Also applies to: 501-583, 587-668, 672-754

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@assets/js/erlang/unicode.mjs` around lines 271 - 354, The four functions
characters_to_nfc_binary/1, characters_to_nfd_binary/1,
characters_to_nfkc_binary/1, and characters_to_nfkd_binary/1 duplicate the same
helpers (validateListRest, handleConversionError, handleInvalidUtf8) and differ
only by the normalization form string; extract a factory like
makeNormalizationBinaryFn(form) that returns the function implementing the
shared logic and uses the form when calling String.prototype.normalize (i.e.,
replace hardcoded "NFC" with the parameter), then replace each of the four
exported entries with makeNormalizationBinaryFn("NFC"),
makeNormalizationBinaryFn("NFD"), makeNormalizationBinaryFn("NFKC"), and
makeNormalizationBinaryFn("NFKD") respectively, keeping references to
Erlang_Unicode["characters_to_binary/3"], Bitstring.toText,
Bitstring.getValidUtf8Length, Type.bitstring, and Type.tuple unchanged inside
the factory.