code: function patch(node, languages) {
      var data = node.data || {};
      var primary = languages[0][0];
  
      data.language = primary === 'und' ? null : primary;
      data.languages = languages;
  
      node.data = data;
  }
docs: Patch a `language` and `languages` properties on `node`.
  
  @param {NLCSTNode} node - Node.
  @param {Array.<Array.<string, number>>} languages - Languages.