text: "use strict";
  
  const DOMException = require("domexception");
  const idlUtils = require("../generated/utils.js");
  const attributes = require("../attributes.js");
  const { HTML_NS } = require("../helpers/namespaces");
  
  exports.implementation = class NamedNodeMapImpl {
    constructor(args, privateData) {
      this._element = privateData.element;
    }
    get _attributeList() {
      return this._element._attributeList;
    }
  
    get [idlUtils.supportedPropertyIndices]() {
      return this._attributeList.keys();
    }
    get length() {
      return this._attributeList.length;
    }
    item(index) {
      if (index >= this._attributeList.length) {
        return null;
      }
      return this._attributeList[index];
    }
  
    get [idlUtils.supportedPropertyNames]() {
      const names = new Set(this._attributeList.map(a => a._qualifiedName));
      const el = this._element;
      if (el._namespaceURI === HTML_NS && el._ownerDocument._parsingMode === "html") {
        for (const name of names) {
          const lowercaseName = name.toLowerCase();
          if (lowercaseName !== name) {
            names.delete(name);
          }
        }
      }
      return names;
    }
    getNamedItem(qualifiedName) {
      return attributes.getAttributeByName(this._element, qualifiedName);
    }
    getNamedItemNS(namespace, localName) {
      return attributes.getAttributeByNameNS(this._element, namespace, localName);
    }
    setNamedItem(attr) {
      return attributes.setAttribute(this._element, attr);
    }
    setNamedItemNS(attr) {
      return attributes.setAttribute(this._element, attr);
    }
    removeNamedItem(qualifiedName) {
      const attr = attributes.removeAttributeByName(this._element, qualifiedName);
      if (attr === null) {
        throw new DOMException("Tried to remove an attribute that was not present", "NotFoundError");
      }
      return attr;
    }
    removeNamedItemNS(namespace, localName) {
      const attr = attributes.removeAttributeByNameNS(this._element, namespace, localName);
      if (attr === null) {
        throw new DOMException("Tried to remove an attribute that was not present", "NotFoundError");
      }
      return attr;
    }
  };
  