Json to html for himalaya

mariana.js

var mariana = {
  parse : function(json){
    return mariana.checkFragment(json);
  },
  checkFragment : function(arr){
    var out = '';
    
    for(fragment of arr){ 
      switch(fragment.kind){
        case "element": out += mariana.element(fragment); break;
        case "text": out += fragment.content; break;
        case "comment": out += '<!--'+fragment.content+'-->'; break;
      }
    }
    
    return out;
  },
  element : function(obj){
  	var out = '<'+obj.tagName+mariana.attributes(obj)+'>';
    var voidTags = [
	"!doctype", "area", "base", "br", "col", "command", 
	"embed", "hr", "img", "input", "keygen", "link", 
	"meta", "param", "source", "track", "wbr"];
    
    if(voidTags.indexOf(obj.tagName) === -1){
    
      if(typeof obj.children !== 'undefined'){
        out += mariana.checkFragment(obj.children);
      }
    
      out += '</'+obj.tagName+'>';
    }
    
    return out;
  },
  attributes : function(obj){
      var out = [];
    
      if(typeof obj.id !== 'undefined'){
        out[out.length] = 'id="'+obj.id+'"'; 
      }

      if(typeof obj.className !== 'undefined'){
        out[out.length] = 'class="'+obj.className.join(' ')+'"';
      }
    
      if(typeof obj.dataset !== 'undefined'){
        for(key in obj.dataset){
          out[out.length] = 'data-'+key+'="'+obj.dataset[key]+'"'; 
        }
      }
    
      var excluded = ['id', 'tagName', 'className', 'dataset', 'children', 'kind'];
    
      for(key in obj){
        if(excluded.indexOf(key) == -1){
          out[out.length] = key+'="'+obj[key]+'"'; 
        }
      }

      return out.length !== 0 ? ' '+out.join(' ') : '';
  }
};