Function parseDTDMarkupDeclaration

xml/_parse_sync.ts:289–350

* Parse a DTD markup declaration (<!ENTITY, <!ELEMENT, <!ATTLIST, <!NOTATION, or comment).

()

   * Parse a DTD markup declaration (<!ENTITY, <!ELEMENT, <!ATTLIST, <!NOTATION, or comment).
   */
  function parseDTDMarkupDeclaration(): void {
    if (pos >= len) {
      error("Unexpected end of input in DTD declaration");
    }

    // Check for comment
    if (input.charCodeAt(pos) === CC_DASH) {
      pos++;
      if (pos >= len || input.charCodeAt(pos) !== CC_DASH) {
        error("Expected '--' to start comment in DTD");
      }
      pos++;
      // Skip comment content
      while (pos < len) {
        if (
          input.charCodeAt(pos) === CC_DASH &&
          pos + 1 < len &&
          input.charCodeAt(pos + 1) === CC_DASH
        ) {
          pos += 2;
          if (pos >= len || input.charCodeAt(pos) !== CC_GT) {
            error("Cannot use '--' within XML comments (XML 1.0 §2.5)");
          }
          pos++;
          return;
        }
        pos++;
      }
      error("Unterminated comment in DTD");
    }

    // Read declaration keyword (ENTITY, ELEMENT, ATTLIST, NOTATION)
    const kwStart = pos;
    while (
      pos < len &&
      ((input.charCodeAt(pos) >= 65 && input.charCodeAt(pos) <= 90) || // A-Z
        (input.charCodeAt(pos) >= 97 && input.charCodeAt(pos) <= 122)) // a-z
    ) {
      pos++;
    }
    const keyword = input.slice(kwStart, pos);

    if (
      keyword !== "ENTITY" && keyword !== "ELEMENT" &&
      keyword !== "ATTLIST" && keyword !== "NOTATION"
    ) {
      error(`Unknown DTD declaration type '<!${keyword}'`);
    }

    // Must have whitespace after keyword
    if (pos >= len || !isWhitespace(input.charCodeAt(pos))) {
      error(`Missing whitespace after '<!${keyword}'`);
    }

    // For ENTITY declarations, extract the entity name and value
    if (keyword === "ENTITY") {
      parseEntityDeclaration();
    } else {