docs: private void parseAttlistDecl() throws Exception {
          String elementName;
  
          requireWhitespace();
          elementName = readNmtoken(true);
          boolean white = tryWhitespace();
          while (!tryRead('>')) {
              if (!white) {
                  fatal("whitespace required before attribute definition");
              }
              parseAttDef(elementName);
              white = tryWhitespace();
          }
      }