diff --git a/src/codegen.inc.php b/src/codegen.inc.php
index 34c6fed..22fc6fa 100644
--- a/src/codegen.inc.php
+++ b/src/codegen.inc.php
@@ -84,15 +84,21 @@ function _add_twig_support(\Twig\Environment $twig)
     }
   ));
   $twig->addFunction(new \Twig\TwigFunction('data2value', 
-    function($name, \mtgType $type, $buf, $prefix = '', $tokens = array(), $as_is = false, $postfix = '') 
+    function($val, \mtgType $type, $data, $tokens) 
     { 
-      return data2value($name, $type, $buf, $prefix, $tokens, $as_is, $postfix);
+      return data2value($val, $type, $data, $tokens);
     }
   ));
   $twig->addFunction(new \Twig\TwigFunction('value2data', 
+    function($val, \mtgType $type, $data, $tokens = array()) 
+    { 
+      return value2data($val, $type, $data, $tokens);
+    }
+  ));
+  $twig->addFunction(new \Twig\TwigFunction('data_normalize', 
     function($name, \mtgType $type, $buf, $prefix = '', $tokens = array()) 
     { 
-      return value2data($name, $type, $buf, $prefix, $tokens);
+      return data_normalize($name, $type, $buf, $prefix, $tokens);
     }
   ));
 }
@@ -147,6 +153,41 @@ function apply_filters($token_prefix, $field_name, array $tokens, $val, $add_ass
   return $str;
 }
 
+function apply_filters_v2($token_prefix, $field_name, array $tokens, $val) : string
+{
+  $str = $val;
+  foreach($tokens as $token => $args_json)
+  {
+    if(strpos($token, $token_prefix) === false)
+      continue;
+
+    $filter_func = '\metagen_php\\' . $token;
+
+    if(function_exists($filter_func))
+    {
+      $args = null;
+      if($args_json && 
+        ((strpos($args_json, '[') === 0 && strlen($args_json) > 1 && $args_json[strlen($args_json)-1] === ']') || 
+         (strpos($args_json, '{') === 0 && strlen($args_json) > 1 && $args_json[strlen($args_json)-1] === '}')))
+      {
+        $args = json_decode($args_json, true);
+        if(!is_array($args))
+          throw new Exception("Bad filter '$token' args: '$args_json'");
+      }
+      else
+        $args = $args_json;
+
+      $str = "$filter_func($str, '$field_name', \$data, " . str_replace("\n", "",  var_export($args, true)) . ")";
+    }
+    else
+      throw new Exception("No such filter '$filter_func'");
+  }
+  if($str !== $val)
+    return "{$val} = " . $str; 
+  else
+    return '';
+}
+
 function apply_array_filters($field_name, array $tokens, $val, $add_assoc_check = true)
 {
   return apply_filters("fltarr_", $field_name, $tokens, $val, $add_assoc_check);
@@ -157,148 +198,100 @@ function apply_value_filters($field_name, array $tokens, $val, $add_assoc_check
   return apply_filters("flt_", $field_name, $tokens, $val, $add_assoc_check);
 }
 
+function apply_array_filters_v2($field_name, array $tokens, $val) : string
+{
+  return apply_filters_v2("fltarr_", $field_name, $tokens, $val);
+}
+
+function apply_value_filters_v2($field_name, array $tokens, $val) : string
+{
+  return apply_filters_v2("flt_", $field_name, $tokens, $val);
+}
+
 //TODO: move it to template
-function data2value($name, \mtgType $type, $buf, $prefix = '', $tokens = array(), $as_is = false, $postfix = '', $indent = '')
+function data2value(string $val, \mtgType $type, string $data, array $tokens, bool $inside_loop = false)
 {
   $str = '';
   $tmp_val = '$tmp_val__';
-  $pname = $prefix.$name;
 
-  $cond_indent = $indent."  ";
-
-  $default_value_arg = array_key_exists('default', $tokens) ? ', '.default_value($tokens['default']) : '';
-  if($type instanceof \mtgMetaStruct)
+  if(!$inside_loop)
   {
-    $default = array_key_exists('default', $tokens) ? $tokens['default'] : null;
-    if($default)
-    {
-      $default = json_decode($default, true);
-      if(is_array($default))
-      {
-        $default = str_replace("\n", "",  var_export($default, true));
-        $default_value_arg = ", \$assoc ? $default : array_values($default)";
-      }
-      else if($default === null)
-      {
-        $default_value_arg = ", null";
-      }
-      else
-        throw new Exception("Bad default struct: " . $tokens['default']);
-    }
+    $str .= "{$tmp_val} = current({$data});\n";
+    $str .= "if({$tmp_val} === false && key({$data}) === null) throw new Exception(\"No more data\");\n";
+    $str .= "next({$data});\n\n";
   }
 
-  $str .= "\n";
-
-  if($as_is)
-    $tmp_val = $buf;
-  else
-    $str .= $indent."{$tmp_val} = \metagen_php\array_extract_val({$buf}, \$assoc, '{$name}' {$default_value_arg});\n";
-
-  if($type instanceof \mtgBuiltinType)
+  if($type instanceof \mtgBuiltinType || $type instanceof \mtgMetaEnum)
   {
-    $str .= $cond_indent."{$tmp_val} = " . apply_value_filters($name, $tokens, "{$tmp_val}"). ";\n";
-    $str .= $cond_indent."{$pname} = \metagen_php\\val_{$type}({$tmp_val});\n";
+    $str .= "{$val} = {$tmp_val};\n";
   }
   else if($type instanceof \mtgMetaStruct)
   {
-    $str .= $cond_indent."if({$tmp_val} === null) {\n";
-    $str .= $cond_indent."  {$pname} = null; \n";
-    $str .= $cond_indent."} else {\n";
-    $str .= $cond_indent."{$tmp_val} = " . apply_value_filters($name, $tokens, "{$tmp_val}"). ";\n";
-    $str .= $cond_indent."\$tmp_sub_arr__ = \metagen_php\\val_arr({$tmp_val});\n";
+    $str .= "if({$tmp_val} === null)\n";
+    $str .= "  {$val} = null;\n";
+    $str .= "else\n";
+    $str .= "{\n";
     if(array_key_exists('virtual', $tokens))
     {
-      $str .= $cond_indent."\$vclass__ = AutogenBundle::getClassName(\metagen_php\\val_uint32(\metagen_php\array_extract_val(\$tmp_sub_arr__, \$assoc, '\$id', {$type->getClassId()})));\n";
-      $str .= $cond_indent."if(!is_a(\$vclass__, '{$type->getName()}', true)) throw new Exception(\"'\$vclass__' is not subclass of '{$type->getName()}'\");\n";
-      $str .= $cond_indent."{$pname} = new \$vclass__(\$tmp_sub_arr__, \$assoc);\n";
+      $str .= "  \$vclass__ = AutogenBundle::getClassName(array_shift({$tmp_val}));\n";
+      $str .= "  if(!is_a(\$vclass__, '{$type->getName()}', true)) throw new Exception(\"'\$vclass__' is not subclass of '{$type->getName()}'\");\n";
+      $str .= "  {$val} = new \$vclass__();\n";
+      $str .= "  {$val}->import({$tmp_val});\n";
     }
     else
     {
-      $str .= $cond_indent."  {$pname} = new {$type}(\$tmp_sub_arr__, \$assoc);\n";
+      $str .= "  {$val} = new {$type}();\n";
+      $str .= "  {$val}->import({$tmp_val});\n";
     }
-    $str .= "}";
+    $str .= "}\n";
   }
   else if($type instanceof \mtgArrType)
   {
-    //TODO: maybe filters should be applied to the whole array as well?
-    $str .= $cond_indent."{$tmp_val} = " . apply_array_filters($name, $tokens, "{$tmp_val}"). ";\n";
-    $str .= $cond_indent."\$tmp_arr__ = \metagen_php\\val_arr({$tmp_val});\n";
-    $str .= $cond_indent."foreach(\$tmp_arr__ as \$tmp_arr_item__)\n";
-    $str .= $cond_indent."{\n";
-    //NOTE: removing default for field
-    unset($tokens['default']);
-    $str .= data2value('$tmp__', $type->getValue(), "\$tmp_arr_item__", '', $tokens, true, "{$pname}[] = \$tmp__;", $cond_indent."  ") . "\n";
-    $str .= $cond_indent."}\n";
-  }
-  else if($type instanceof \mtgMetaEnum)
-  {
-    $str .= $cond_indent."{$tmp_val} = " . apply_value_filters($name, $tokens, "{$tmp_val}"). ";\n";
-    $str .= $cond_indent."{$pname} = \metagen_php\\val_enum('$type', {$tmp_val}, false);\n";
+    $str .= "\$tmp_arr__ = {$tmp_val};\n";
+    $str .= "foreach(\$tmp_arr__ as {$tmp_val})\n";
+    $str .= "{\n";
+    $str .= data2value('$tmp__', $type->getValue(), "\$tmp_arr_item__", $tokens, true) . "\n";
+    $str .= "{$val}[] = \$tmp__;\n";
+    $str .= "}\n";
   }
   else
     throw new Exception("Unknown type '{$type->getName()}'");
 
-  if($postfix)
-    $str .= $cond_indent.$postfix."\n";
-
-  //replacing some garbage
-  $str = str_replace('$tmp_val__ = $tmp_val__;', '', $str);
   return $str;
 }
 
 //TODO: move it to template
-function value2data($name, \mtgType $type, $buf, $prefix = '', $tokens = array(), $indent = '')
+function value2data(string $val, \mtgType $type, string $data, $tokens = array())
 {
-  $pname = $prefix.$name;
-
   $str = '';
-  $str .= "\$__last_var = '$name';";
-  $str .= "\$__last_val = $pname;";
 
   if($type instanceof \mtgBuiltinType)
   {
-    if($type->isNumeric())
-      $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', 1*{$pname});";
-    else if($type->isString())
-      $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', ''.{$pname});";
-    else if($type->isBool())
-      $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', (bool){$pname});";
-    else if($type->isBlob())
-      $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', {$pname});";
-    else
-      throw new Exception("Unknown type '$type'");
+    $str .= "{$data}[] = $val;\n";
   }
   else if($type instanceof \mtgMetaStruct)
   {
     if(array_key_exists('virtual', $tokens))
-      $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', !is_object({$pname}) ? {$pname} : {$pname}->export(\$assoc, true/*virtual*/));";
+      $str .= "{$data}[] = {$val}->export(true/*virtual*/);\n";
     else
-      $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', !is_object({$pname}) ? {$pname} : {$pname}->export(\$assoc));";
+      $str .= "{$data}[] = {$val}->export();\n";
   }
   else if($type instanceof \mtgMetaEnum)
   {
-    $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', 1*{$pname});";
+    $str .= "{$data}[] = $val;\n";
   }
   else if($type instanceof \mtgArrType)
   {
-    $str .= $indent."\$arr_tmp__ = array();\n";
+    $str .= "\$arr_tmp__ = array();\n";
     //NOTE: adding optimization, checking if the first item is array
-    $str .= $indent."if(!\$assoc && {$pname} && is_array(current({$pname})))\n";
-    $str .= $indent."{\n";
-    //$str .= "  \metagen_php\debug('BULK:' . get_class(\$this));\n";
-    $str .= $indent."  \$arr_tmp__ = {$pname};\n";
-    $str .= $indent."}\n";
-    $str .= $indent."else\n";
-    $str .= $indent."  foreach({$pname} as \$idx__ => \$arr_tmp_item__)\n";
-    $str .= $indent."  {\n";
-    $str .= value2data('$arr_tmp_item__', $type->getValue(), "\$arr_tmp__", "", $tokens, $indent."    ") . "\n";
-    $str .= $indent."    if(\$assoc)\n";
-    $str .= $indent."    {\n";
-    $str .= $indent."      \$arr_tmp__[] =  \$arr_tmp__['\$arr_tmp_item__'];\n";
-    $str .= $indent."      unset(\$arr_tmp__['\$arr_tmp_item__']);\n";
-    $str .= $indent."    }\n";
-    $str .= $indent."  }\n";
-    $str .= $indent."\metagen_php\array_set_value({$buf}, \$assoc, '$name', \$arr_tmp__);\n";
+    $str .= "if({$val} && is_array(current({$val})))\n";
+    $str .= "  \$arr_tmp__ = {$val};\n";
+    $str .= "else\n";
+    $str .= "  foreach({$val} as \$arr_tmp_item__)\n";
+    $str .= "  {\n";
+    $str .= value2data("\$arr_tmp_item__", $type->getValue(), "\$arr_tmp__", $tokens) . "\n";
+    $str .= "  }\n";
+    $str .= "{$data}[] = \$arr_tmp__;\n";
   }
   else
     throw new Exception("Unknown type '{$type->getName()}'");
@@ -310,3 +303,90 @@ function is_null_str($default)
 {
   return is_string($default) && json_decode($default, true) === null;
 }
+
+function data_normalize($name, \mtgType $type, $buf, $dst, $tokens = array(), $tmp_val = '$tmp_val__')
+{
+  $str = '';
+
+  $default_value_arg = array_key_exists('default', $tokens) ? default_value($tokens['default']) : "null";
+
+  if($type instanceof \mtgMetaStruct)
+  {
+    $default = array_key_exists('default', $tokens) ? $tokens['default'] : null;
+    if($default)
+    {
+      $default = json_decode($default, true);
+      if(is_array($default))
+      {
+        $default = str_replace("\n", "",  var_export($default, true));
+        $default_value_arg = "$default";
+      }
+      else if($default === null)
+      {
+        $default_value_arg = "null";
+      }
+      else
+        throw new Exception("Bad default struct: " . $tokens['default']);
+    }
+  }
+
+  $str .= "\n";
+
+  if($name !== null)
+    $str .= "{$tmp_val} = {$buf}['{$name}'] ?? {$default_value_arg};\n";
+
+  if($type instanceof \mtgBuiltinType)
+  {
+    $str .= apply_value_filters_v2($name, $tokens, "{$tmp_val}"). ";\n";
+    $str .= "{$dst}[] = \metagen_php\\val_{$type}({$tmp_val});\n";
+  }
+  else if($type instanceof \mtgMetaStruct)
+  {
+    $str .= "if({$tmp_val} === null) {\n";
+    $str .= "  {$dst}[] = null; \n";
+    $str .= "} else {\n";
+    $str .= apply_value_filters_v2($name, $tokens, "{$tmp_val}"). ";\n";
+    $str .= "\$tmp_sub_arr__ = \metagen_php\\val_arr({$tmp_val});\n";
+    if(array_key_exists('virtual', $tokens))
+    {
+      $str .= "\$vclass_id__ = \metagen_php\\val_uint32(\$tmp_sub_arr__['\$id'] ?? {$type->getClassId()});\n";
+      $str .= "\$vclass__ = AutogenBundle::getClassName(\$vclass_id__);\n";
+      $str .= "if(!is_a(\$vclass__, '{$type->getName()}', true)) throw new Exception(\"'\$vclass__' is not subclass of '{$type->getName()}'\");\n";
+      $str .= "\$tmp_sub_mapped__ = array(\$vclass_id__);\n";
+      $str .= "call_user_func_array([\$vclass__, 'normalize'], array(&\$tmp_sub_arr__, &\$tmp_sub_mapped__));\n";
+      $str .= "{$dst}[] = \$tmp_sub_mapped__;\n";
+    }
+    else
+    {
+      $str .= "\$tmp_sub_mapped__ = array();\n";
+      $str .= "{$type}::normalize(\$tmp_sub_arr__, \$tmp_sub_mapped__);\n";
+      $str .= "{$dst}[] = \$tmp_sub_mapped__;\n";
+    }
+    $str .= "}";
+  }
+  else if($type instanceof \mtgArrType)
+  {
+    //TODO: maybe filters should be applied to the whole array as well?
+    $str .= apply_array_filters_v2($name, $tokens, "{$tmp_val}"). ";\n";
+    $str .= "\$tmp_arr__ = \metagen_php\\val_arr({$tmp_val});\n";
+    $str .= "\$tmp_dst_arr__ = array();\n";
+
+    $str .= "foreach(\$tmp_arr__ as \$tmp_arr_item__)\n";
+    $str .= "{\n";
+    //NOTE: removing default for field
+    unset($tokens['default']);
+    $str .= data_normalize(null, $type->getValue(), "\$tmp_arr_item__", "\$tmp_dst_arr__", $tokens, "\$tmp_arr_item__") . "\n";
+    $str .= "}\n";
+    $str .= "{$dst}[] = \$tmp_dst_arr__;\n";
+  }
+  else if($type instanceof \mtgMetaEnum)
+  {
+    $str .= apply_value_filters_v2($name, $tokens, "{$tmp_val}"). ";\n";
+    $str .= "{$dst}[] = \metagen_php\\val_enum('$type', {$tmp_val}, false);\n";
+  }
+  else
+    throw new Exception("Unknown type '{$type->getName()}'");
+
+  return $str;
+}
+
diff --git a/src/data_utils.inc.php b/src/data_utils.inc.php
index c494dad..4c12c66 100644
--- a/src/data_utils.inc.php
+++ b/src/data_utils.inc.php
@@ -2,6 +2,36 @@
 namespace metagen_php;
 use Exception;
 
+function data_get_val(&$arr_or_obj, $name)
+{
+  if(is_array($arr_or_obj))
+    return $arr_or_obj[$name];
+  else if(is_object($arr_or_obj))
+    return $arr_or_obj->$name;
+  else
+    throw new Exception("Not an array nor an object");
+}
+
+function data_set_val(&$arr_or_obj, $name, $val)
+{
+  if(is_array($arr_or_obj))
+    $arr_or_obj[$name] = $val;
+  else if(is_object($arr_or_obj))
+    $arr_or_obj->$name = $val;
+  else
+    throw new Exception("Not an array nor an object");
+}
+
+function data_get_keys(&$arr_or_obj) : array
+{
+  if(is_array($arr_or_obj))
+    return array_keys($arr_or_obj);
+  else if(is_object($arr_or_obj))
+    return array_keys(get_object_vars($arr_or_obj));
+  else
+    throw new Exception("Not an array nor an object");
+}
+
 function array_extract_val(&$arr, $assoc, $name)
 {
   if(!is_array($arr))
diff --git a/tpl/macro.twig b/tpl/macro.twig
index 6abfe5f..f8bd38c 100644
--- a/tpl/macro.twig
+++ b/tpl/macro.twig
@@ -48,12 +48,9 @@ class {{o.name}} {{o.parent ? 'extends ' ~ o.parent.name}}
     return $flds;
   }
 
-  function __construct(&$data = null, $assoc = false)
+  function __construct()
   {
     {{_self.fields_init(o)}}
-
-    if(!is_null($data))
-      $this->import($data, $assoc);
   }
 
   function getClassId()
@@ -61,57 +58,72 @@ class {{o.name}} {{o.parent ? 'extends ' ~ o.parent.name}}
     return self::CLASS_ID;
   }
 
-  function import(&$data, $assoc = false, $root = true)
+  function import(array &$data)
+  {
+    $this->_import($data, true);
+  }
+
+  function _import(array &$data, $root = true) : int
+  {
+    if(!is_array($data))
+      throw new Exception("Bad data: $data");
+
+    if($root)
+      reset($data);
+
+    $IDX = 0;
+
+    try
+    {
+      {{_self.import_fields(o)}}
+    }
+    catch(Exception $e)
+    {
+      $FIELDS = self::CLASS_FIELDS();
+      throw new Exception($e->getMessage() . " < {$FIELDS[$IDX]} < ({{o.name}})");
+    }
+    return $IDX;
+  }
+
+  function export($virtual = false) : array
+  {
+    $data = array();
+    $this->_export($data, $virtual);
+    return $data;
+  }
+
+  function _export(array &$data, $virtual = false)
+  {
+    if($virtual)
+      $data[] = $this->getClassId(); 
+      
+    {{_self.export_fields(o)}}
+  }
+
+  static function normalize(array &$data, array &$mapped, bool $root = true) : int
   {
     $IDX = -1;
 
     try
     {
-      if(!is_array($data))
-        throw new Exception("Bad data: $data");
-      try
-      {
-        $IDX = 0;
-        {{_self.import_fields(o)}}
-      }
-      catch(Exception $e)
-      {
-        $FIELDS = self::CLASS_FIELDS();
-        throw new Exception($e->getMessage() . " < {$FIELDS[$IDX]}");
-      }
-      if($root && $assoc && sizeof($data) > 0)
-        throw new Exception("Junk fields: " . implode(',', array_keys($data)));
+      $IDX = 0;
+{%- if o.parent ~%}
+      $IDX = parent::normalize($data, $mapped, false);
+{%- endif ~%}
+
+{%- for f in o.fields ~%}
+      {{data_normalize(f.name, f.type, '$data', '$mapped', f.tokens)}}
+      ++$IDX;
+{%- endfor ~%}
     }
     catch(Exception $e)
     {
-      throw new Exception($e->getMessage() . " < ({{o.name}})");
+      $FIELDS = self::CLASS_FIELDS();
+      throw new Exception($e->getMessage() . " < {$FIELDS[$IDX]} < ({{o.name}})");
     }
+    
     return $IDX;
   }
-
-  function export($assoc = false, $virtual = false)
-  {
-    $data = array();
-    $this->fill($data, $assoc, $virtual);
-    return $data;
-  }
-
-  function fill(&$data, $assoc = false, $virtual = false)
-  {
-    if($virtual)
-      \metagen_php\array_set_value($data, $assoc, 'vclass__', $this->getClassId());
-    try
-    {
-      $__last_var = null;
-      $__last_val = null;
-
-      {{_self.export_fields(o)}}
-    }
-    catch(Exception $e)
-    {
-      throw new Exception("[{{o.name}}]\n->$__last_var\n" . serialize($__last_val) . "\n\t" . $e->getMessage());
-    }
-  }
 }
 
 {% endmacro %}
@@ -231,22 +243,20 @@ array_merge(parent::CLASS_FIELDS_PROPS(),
 
 {% macro import_fields(o) %}
 {%- if o.parent -%}
-  $IDX = parent::import($data, $assoc, false);
+  $IDX = parent::_import($data, false);
 {%- endif -%}
 {%- for f in o.fields ~%}
-  {{data2value(f.name, f.type, '$data', '$this->', f.tokens)}}
+  {{data2value('$this->'~f.name, f.type, '$data', f.tokens)}}
   ++$IDX;
 {%- endfor -%}
 {% endmacro %}
 
 {% macro export_fields(o) %}
 {%- if o.parent -%}
-  $__last_var = 'parent';
-  $__last_val = '<<skipped>>';
-  parent::fill($data, $assoc, false);
+  parent::_export($data, false);
 {%- endif -%}
 {%- for f in o.fields ~%}
-  {{value2data(f.name, f.type, '$data', '$this->', f.tokens)}}
+  {{value2data('$this->'~f.name, f.type, '$data', f.tokens)}}
 {%- endfor -%}
 {% endmacro %}