diff --git a/enum.inc.php b/enum.inc.php
new file mode 100644
index 0000000..d52c29e
--- /dev/null
+++ b/enum.inc.php
@@ -0,0 +1,55 @@
+<?php
+
+class mtgMetaEnum extends mtgUserType
+{
+  private $values = array();
+
+  function validate(mtgMetaInfo $meta) {}
+
+  function addValue($value_name, $value)
+  {
+    if(isset($this->values[$value_name]))
+      throw new Exception("Enum '{$this->name}' already has value with name '{$value_name}'");
+
+    if(in_array($value, $this->values))
+      throw new Exception("Enum '{$this->name}' already has value '{$value}'");
+
+    $this->values[$value_name] = $value; 
+  }
+
+  function calcOrValue($or_keys)
+  {
+    $res = 0;
+    foreach($or_keys as $value_name)
+    {
+      if(!isset($this->values[$value_name]))
+        throw new Exception("Enum '{$this->name}' has no value '{$value_name}'");
+      $res |= $this->values[$value_name];
+    }
+
+    return $res;
+  }
+
+  function addOrValues($values)
+  {
+    foreach($values as $value_name => $or_keys)
+      $this->addValue($value_name, $this->calcOrValue($or_keys));
+  }
+
+  function getValues()
+  {
+    return $this->values;
+  }
+
+  function override(mtgMetaEnum $other)
+  {
+    $this->tokens = array_merge($this->tokens, $other->getTokens());
+    $this->values = array_merge($this->values, $other->getValues());
+  }
+
+  function replace(mtgMetaEnum $other)
+  {
+    $this->tokens = $other->getTokens();
+    $this->values = $other->getValues();
+  }
+} 
diff --git a/func.inc.php b/func.inc.php
new file mode 100644
index 0000000..5028e10
--- /dev/null
+++ b/func.inc.php
@@ -0,0 +1,77 @@
+<?php
+
+class mtgMetaFunc extends mtgMetaUnit implements mtgType
+{
+  private string $name;
+  private $args = array();
+  private $ret_type;
+
+  function __construct($name)
+  {
+    $this->name = $name;
+  }
+
+  function validate(mtgMetaInfo $meta)
+  {}
+
+  function __toString()
+  {
+    $str = "func ";
+
+    $str .= $this->name.'(';
+    foreach($this->getArgs() as $arg)
+      $str .= $arg->getType() . ',';
+    $str = rtrim($str, ',');
+    $str .= ')';
+    if($ret_type = $this->getReturnType())
+      $str .= ':'.$ret_type;
+    return $str;
+  }
+
+  function setReturnType(mtgTypeRef $type)
+  {
+    $this->ret_type = $type;
+  }
+
+  function getReturnType() : ?mtgType
+  {
+    return $this->ret_type ? $this->ret_type->resolve() : null;
+  }
+
+  function getName() : string
+  {
+    return $this->name;
+  }
+
+  function getArgs()
+  {
+    return $this->args;
+  }
+
+  function setArgs(array $args)
+  {
+    foreach($args as $arg)
+      $this->addArg($arg);
+  }
+
+  function addArg(mtgMetaField $arg)
+  {
+    if($this->hasArg($arg->getName()))
+      throw new Exception("Func '{$this->name}' already has arg '{$arg->getName()}'");
+
+    $this->args[$arg->getName()] = $arg;
+  }
+
+  function hasArg($name)
+  {
+    return isset($this->args[$name]);
+  }
+
+  function getArg($name)
+  {
+    if(!isset($this->args[$name]))
+      throw new Exception("No such arg '$name'");
+    return $this->args[$name];
+  }
+}
+
diff --git a/interface.inc.php b/interface.inc.php
new file mode 100644
index 0000000..c774959
--- /dev/null
+++ b/interface.inc.php
@@ -0,0 +1,54 @@
+<?php
+
+class mtgMetaInterface extends mtgUserType
+{
+  protected $funcs = array();
+  protected $implements = null;
+
+  function __construct($name, array $implements = array(), $tokens = array())
+  {
+    parent::__construct($name);
+
+    $this->implements = $implements;
+    $this->tokens = $tokens;
+  }
+
+  function validate(mtgMetaInfo $meta) {}
+
+  function getImplements()
+  {
+    if(!$this->implements)
+      return array();
+
+    $imps = array();
+    foreach($this->implements as $imp)
+      $imps[] = $imp->resolve();
+    return $imps;
+  }
+
+  function getFuncs()
+  {
+    return $this->funcs;
+  }
+
+  function addFunc(mtgMetaFunc $fn)
+  {
+    if($this->hasFunc($fn->getName()))
+      throw new Exception("Interface '{$this->name}' already has func '{$fn->getName()}'");
+
+    $this->funcs[$fn->getName()] = $fn;
+  }
+
+  function hasFunc($name)
+  {
+    return isset($this->funcs[$name]);
+  }
+
+  function getFunc($name)
+  {
+    if(!isset($this->funcs[$name]))
+      throw new Exception("No such funcs '$name'");
+    return $this->funcs[$name];
+  }
+}
+
diff --git a/metagen.inc.php b/metagen.inc.php
index 5a2a708..9fc0293 100644
--- a/metagen.inc.php
+++ b/metagen.inc.php
@@ -1,104 +1,97 @@
 <?php
+require_once(__DIR__ . '/type.inc.php');
+require_once(__DIR__ . '/scope.inc.php');
+require_once(__DIR__ . '/struct.inc.php');
+require_once(__DIR__ . '/enum.inc.php');
+require_once(__DIR__ . '/func.inc.php');
+require_once(__DIR__ . '/interface.inc.php');
+require_once(__DIR__ . '/service.inc.php');
+require_once(__DIR__ . '/util.inc.php');
 
-interface mtgType
+class mtgMetaInfo
 {
-  function getName();
-}
+  public static $BUILTIN_TYPES = array(
+    'int8', 'int16', 'int32', 'uint8', 'uint16', 'uint32', 
+    'float', 'double', 'uint64', 'int64', 'bool', 'string', 'blob'
+  );
 
-interface mtgScope
-{
-  function findSymbol(string $name) : ?mtgMetaUnit;
-}
+  private $units = array();
 
-class mtgMultiScope implements mtgScope
-{
-  private array $scopes = array();
+  private $factory_types = array();
 
-  function addScope(mtgScope $scope)
+  function addUnit(mtgMetaInfoUnit $unit)
   {
-    $this->scopes[] = $scope;
+    if(isset($this->units[$unit->object->getName()]))
+      throw new Exception("Meta info unit '{$unit->object->getName()}' already defined in file '{$this->units[$unit->object->getName()]->file}'");
+
+    $this->units[$unit->object->getName()] = $unit;
+
+    if($unit->object instanceof mtgMetaStruct)
+      $this->_registerFactoryStruct($unit->object);
+    else if($unit->object instanceof mtgMetaService)
+    {
+      foreach($unit->object->getUserTypes() as $user_type)
+        if($user_type instanceof mtgMetaStruct)
+          $this->_registerFactoryStruct($user_type);
+    }
   }
 
-  function findSymbol(string $name) : ?mtgMetaUnit
+  function delUnit(mtgMetaInfoUnit $unit)
   {
-    foreach($this->scopes as $scope)
+    unset($this->units[$unit->object->getName()]);
+
+    if($unit->object instanceof mtgMetaStruct)
+      $this->_unregisterFactoryStruct($unit->object);
+    else if($unit->object instanceof mtgMetaService)
     {
-      $unit = $scope->findSymbol($name);
-      if($unit)
-        return $unit;
+      foreach($unit->object->getUserTypes() as $user_type)
+        if($user_type instanceof mtgMetaStruct)
+          $this->_unregisterFactoryStruct($user_type);
     }
+  }
+
+  function getUnits() : array
+  {
+    return $this->units;
+  }
+
+  function findUnit($id) : ?mtgMetaInfoUnit
+  {
+    if(isset($this->units[$id]))
+      return $this->units[$id];
     return null;
   }
-}
 
-class mtgTypeRef implements mtgType
-{
-  private static $unresolved = array();
-
-  private $name;
-  private $scope;
-  private $resolved;
-  private $origin;
-
-  function __construct($name_or_resolved, mtgScope $scope = null, mtgOrigin $origin = null)
+  function getUnit($id) : mtgMetaInfoUnit
   {
-    if(is_object($name_or_resolved))
-    {
-      if(!($name_or_resolved instanceof mtgType))
-        throw new Exception("Bad type");
-      $this->resolved = $name_or_resolved;
-    }
-    else
-    {
-      $this->name = $name_or_resolved;
-      if(!$scope)
-        throw new Exception("Scope is not set");
-
-      self::$unresolved[] = $this;
-    }
-
-    $this->scope = $scope;
-    $this->origin = $origin ?? new mtgOrigin();
-
+    $unit = $this->findUnit($id);
+    if(!$unit)
+      throw new Exception("Unit '$id' not found");
+    return $unit;
   }
 
-  function getName()
+  private function _registerFactoryStruct(mtgMetaStruct $struct)
   {
-    if($this->resolved)
-      return ''.$this->resolved;
-    else
-      return $this->name;
+    if(isset($this->factory_types[$struct->getClassId()]))
+      throw new Exception("Factory user type with id '{$struct->getClassId()}' already defined for type '{$this->factory_types[$struct->getClassId()]->getName()}'");
+
+    $this->factory_types[$struct->getClassId()] = $struct;
   }
 
-  static function checkAllResolved()
+  private function _unregisterFactoryStruct(mtgMetaStruct $struct)
   {
-    while(sizeof(self::$unresolved) > 0)
-    {
-      $ref = array_shift(self::$unresolved);
-      $resolved = $ref->resolve();
-      if($resolved instanceof mtgMetaFunc && $resolved->getName())
-        throw new Exception("Invalid resolving of named function as type: " . $resolved->getName() . " at " . $ref->origin);
-    }
+    unset($this->factory_types[$struct->getClassId()]);
   }
 
-  function resolve()
+  function getFactoryTypes() : array
   {
-    if($this->resolved)
-      return $this->resolved;
+    return $this->factory_types;
+  }
 
-    $symb = $this->scope->findSymbol($this->name);
-    if($symb)
-    {
-      $this->resolved = $symb;
-      return $this->resolved;
-    }
-    else
-      throw new Exception("{$this->origin} : Symbol '{$this->name}' not found");
-  } 
-
-  function __toString()
+  function validate()
   {
-    return $this->getName();
+    foreach($this->units as $u)
+      $u->object->validate($this);
   }
 }
 
@@ -125,90 +118,25 @@ class mtgMetaInfoUnit
   }
 }
 
-class mtgMetaInfo
-{
-  public static $BUILTIN_TYPES = array(
-    'int8', 'int16', 'int32', 'uint8', 'uint16', 'uint32', 
-    'float', 'double', 'uint64', 'int64', 'bool', 'string', 'blob'
-  );
-
-  private $units = array();
-
-  function addUnit(mtgMetaInfoUnit $unit)
-  {
-    if(isset($this->units[$unit->object->getMetaId()]))
-      throw new Exception("Meta info unit '{$unit->object->getMetaId()}' already defined in file '{$this->units[$unit->object->getMetaId()]->file}'");
-
-    $this->units[$unit->object->getMetaId()] = $unit;
-  }
-
-  function delUnit(mtgMetaInfoUnit $unit)
-  {
-    unset($this->units[$unit->object->getMetaId()]);
-  }
-
-  function getUnits() : array
-  {
-    return $this->units;
-  }
-
-  function findUnit($id) : ?mtgMetaInfoUnit
-  {
-    if(isset($this->units[$id]))
-      return $this->units[$id];
-    return null;
-  }
-
-  function getUnit($id) : mtgMetaInfoUnit
-  {
-    if(isset($this->units[$id]))
-      return $this->units[$id];
-    throw new Exception("Unit '$id' not found");
-  }
-
-  function validate()
-  {
-    foreach($this->units as $u)
-      $u->object->validate($this);
-  }
-}
-
+//NOTE: represents a meta symbol
 abstract class mtgMetaUnit
 {
-  abstract function getMetaId();
-
-  protected $tokens = array();
+  protected ?mtgScope $scope = null;
 
   protected ?mtgOrigin $origin;
 
-  function getTokens()
+  protected $tokens = array();
+
+  abstract function getName() : string;
+
+  function setScope(mtgScope $scope)
   {
-    return $this->tokens;
+    $this->scope = $scope;
   }
 
-  function setTokens(array $tokens)
+  function getScope() : ?mtgScope
   {
-    $this->tokens = $tokens;
-  }
-
-  function setToken(string $name, $val)
-  {
-    $this->tokens[$name] = $val;
-  }
-
-  function delToken(string $name)
-  {
-    unset($this->tokens[$name]);
-  }
-
-  function getToken(string $name)
-  {
-    return $this->hasToken($name) ? $this->tokens[$name] : null; 
-  }
-
-  function hasToken($name)
-  {
-    return array_key_exists($name, $this->tokens);
+    return $this->scope;
   }
 
   function setOrigin(mtgOrigin $origin)
@@ -221,6 +149,36 @@ abstract class mtgMetaUnit
     return $this->origin;
   }
 
+  function getTokens() : array
+  {
+    return $this->tokens;
+  }
+
+  function setTokens(array $tokens)
+  {
+    $this->tokens = $tokens;
+  }
+
+  function setToken(string $name, mixed $val)
+  {
+    $this->tokens[$name] = $val;
+  }
+
+  function delToken(string $name)
+  {
+    unset($this->tokens[$name]);
+  }
+
+  function getToken(string $name) : mixed
+  {
+    return $this->hasToken($name) ? $this->tokens[$name] : null; 
+  }
+
+  function hasToken(string $name) : bool
+  {
+    return array_key_exists($name, $this->tokens);
+  }
+
   abstract function validate(mtgMetaInfo $meta);
 }
 
@@ -241,842 +199,3 @@ class mtgOrigin
   }
 }
 
-abstract class mtgUserType extends mtgMetaUnit implements mtgType
-{
-  protected $name;
-
-  function __construct($name)
-  {
-    $this->name = $name;
-  }
-
-  function getMetaId()
-  {
-    return $this->name;
-  }
-
-  function getName()
-  {
-    return $this->name;
-  }
-
-  function setName($name)
-  {
-    $this->name = $name;
-  }
-
-  function getClassId()
-  {
-    if($this->hasToken('class_id'))
-      return $this->getToken('class_id');
-
-    //TODO: migrate to crc32 from crc28
-    return crc32($this->name) & 0xFFFFFFF;
-  }
-
-  function __toString()
-  {
-    return $this->name;
-  }
-}
-
-class mtgMetaStruct extends mtgUserType
-{
-  protected $fields = array();
-  protected $funcs = array();
-  protected $parent = null;
-  protected $implements = array();
-
-  function __construct($name, array $fields = array(), mtgTypeRef $parent = null, array $tokens = array(), array $implements = array())
-  {
-    parent::__construct($name);
-
-    $this->setFields($fields);
-    $this->parent = $parent;
-    $this->tokens = $tokens;
-    $this->implements = $implements;
-  }
-
-  function validate(mtgMetaInfo $meta)
-  {
-    $parent = $this->getParent();
-    while($parent != null)
-    {
-      foreach($this->fields as $name => $_)
-        if($parent->hasField($name))
-          throw new Exception("{$this->origin} : Parent struct '{$parent->getName()}' already has field '{$name}'");
-
-      foreach($this->funcs as $name => $_)
-        if($parent->hasFunc($name))
-          throw new Exception("{$this->origin} : Parent struct '{$parent->getName()}' already has func '{$name}'");
-
-      $parent = $parent->getParent();
-    }
-
-    $s = new SplObjectStorage();
-    foreach($this->getImplements() as $imp)
-    {
-      if(!($imp instanceof mtgMetaInterface))
-        throw new Exception("{$this->origin} : Not an interface '{$imp}'");
-
-      if($s->contains($imp))
-        throw new Exception("{$this->origin} : Duplicate interface reference '{$imp->getName()}'");
-      $s->attach($imp);
-    }
-
-    foreach($this->funcs as $func)
-    {
-      $func->validate($meta);
-    }
-  }
-
-  function getParent()
-  {
-    return $this->parent ? $this->parent->resolve() : null;
-  }
-
-  function getImplements()
-  {
-    if(!$this->implements)
-      return array();
-
-    $imps = array();
-    foreach($this->implements as $imp)
-      $imps[] = $imp->resolve();
-    return $imps;
-  }
-
-  function getFields()
-  {
-    return $this->fields;
-  }
-
-  function setFields(array $fields, $replace = false)
-  {
-    if($replace)
-      $this->fields = array();
-
-    foreach($fields as $field)
-      $this->addField($field);
-  }
-
-  function addField(mtgMetaField $field)
-  {
-    if($this->hasField($field->getName()))
-      throw new Exception("Struct '{$this->name}' already has field '{$field->getName()}'");
-
-    $this->fields[$field->getName()] = $field;
-  }
-
-  function delField(mtgMetaField $field)
-  {
-    if(isset($this->fields[$field->getName()]))
-      unset($this->fields[$field->getName()]);
-  }
-
-  function hasField($name)
-  {
-    return isset($this->fields[$name]);
-  }
-
-  function getField($name)
-  {
-    if(!isset($this->fields[$name]))
-      throw new Exception("No such field '$name'");
-    return $this->fields[$name];
-  }
-
-  function getFuncs()
-  {
-    return $this->funcs;
-  }
-
-  function addFunc(mtgMetaFunc $fn)
-  {
-    if($this->hasFunc($fn->getName()))
-      throw new Exception("Struct '{$this->name}' already has func '{$fn->getName()}'");
-
-    $this->funcs[$fn->getName()] = $fn;
-  }
-
-  function hasFunc($name)
-  {
-    return isset($this->funcs[$name]);
-  }
-
-  function getFunc($name)
-  {
-    if(!isset($this->funcs[$name]))
-      throw new Exception("No such funcs '$name'");
-    return $this->funcs[$name];
-  }
-
-  //TODO: doesn't belong here
-  function hasTokenInParent($name)
-  {
-    return mtg_try_get_token_in_hierarchy($this, $name, $value);
-  }
-}
-
-class mtgMetaInterface extends mtgUserType
-{
-  protected $funcs = array();
-  protected $implements = null;
-
-  function __construct($name, array $implements = array(), $tokens = array())
-  {
-    parent::__construct($name);
-
-    $this->implements = $implements;
-    $this->tokens = $tokens;
-  }
-
-  function validate(mtgMetaInfo $meta) {}
-
-  function getImplements()
-  {
-    if(!$this->implements)
-      return array();
-
-    $imps = array();
-    foreach($this->implements as $imp)
-      $imps[] = $imp->resolve();
-    return $imps;
-  }
-
-  function getFuncs()
-  {
-    return $this->funcs;
-  }
-
-  function addFunc(mtgMetaFunc $fn)
-  {
-    if($this->hasFunc($fn->getName()))
-      throw new Exception("Interface '{$this->name}' already has func '{$fn->getName()}'");
-
-    $this->funcs[$fn->getName()] = $fn;
-  }
-
-  function hasFunc($name)
-  {
-    return isset($this->funcs[$name]);
-  }
-
-  function getFunc($name)
-  {
-    if(!isset($this->funcs[$name]))
-      throw new Exception("No such funcs '$name'");
-    return $this->funcs[$name];
-  }
-}
-
-class mtgMetaFunc extends mtgMetaUnit implements mtgType
-{
-  private $name;
-  private $args = array();
-  private $ret_type;
-
-  function __construct($name)
-  {
-    $this->name = $name;
-  }
-
-  function validate(mtgMetaInfo $meta)
-  {}
-
-  function getMetaId()
-  {
-    return $this->name;
-  }
-
-  function __toString()
-  {
-    $str = "func ";
-
-    $str .= $this->name.'(';
-    foreach($this->getArgs() as $arg)
-      $str .= $arg->getType() . ',';
-    $str = rtrim($str, ',');
-    $str .= ')';
-    if($ret_type = $this->getReturnType())
-      $str .= ':'.$ret_type;
-    return $str;
-  }
-
-  function setReturnType(mtgTypeRef $type)
-  {
-    $this->ret_type = $type;
-  }
-
-  function getReturnType()
-  {
-    return $this->ret_type ? $this->ret_type->resolve() : null;
-  }
-
-  function getName()
-  {
-    return $this->name;
-  }
-
-  function getArgs()
-  {
-    return $this->args;
-  }
-
-  function setArgs(array $args)
-  {
-    foreach($args as $arg)
-      $this->addArg($arg);
-  }
-
-  function addArg(mtgMetaField $arg)
-  {
-    if($this->hasArg($arg->getName()))
-      throw new Exception("Func '{$this->name}' already has arg '{$arg->getName()}'");
-
-    $this->args[$arg->getName()] = $arg;
-  }
-
-  function hasArg($name)
-  {
-    return isset($this->args[$name]);
-  }
-
-  function getArg($name)
-  {
-    if(!isset($this->args[$name]))
-      throw new Exception("No such arg '$name'");
-    return $this->args[$name];
-  }
-}
-
-class mtgMetaRPC extends mtgMetaUnit
-{
-  private $name;
-  private $code;
-  private $in;
-  private $out;
-
-  function __construct($name, $code, mtgMetaPacket $in, mtgMetaPacket $out, array $tokens = array())
-  {
-    $this->name = $name;
-    $this->code = $code;
-    $this->in = $in;
-    $this->out = $out;
-    $this->tokens = $tokens;
-  }
-
-  function validate(mtgMetaInfo $meta) {}
-
-  function getMetaId()
-  {
-    return $this->code;
-  }
-
-  function getName()
-  {
-    return $this->name;
-  }
-
-  function getCode()
-  {
-    return $this->code;
-  }
-
-  function getNumericCode()
-  {
-    return (int)$this->code;
-  }
-
-  function getReq()
-  {
-    return $this->in;
-  }
-
-  function getRsp()
-  {
-    return $this->out;
-  }
-}
-
-class mtgMetaService extends mtgMetaUnit implements mtgScope
-{
-  private string $name;
-  //for partial services
-  private mtgMultiScope $parent_scope;
-  private $rpcs = array();
-  private $events = array();
-  private $user_types = array();
-  private $partials = array();
-
-  function __construct(string $name, mtgScope $parent_scope, array $tokens = array())
-  {
-    $this->name = $name;
-    $this->parent_scope = new mtgMultiScope();
-    $this->parent_scope->addScope($parent_scope);
-    $this->tokens = $tokens;
-  }
-
-  function getParentScope() : mtgScope
-  {
-    return $this->parent_scope;
-  }
-
-  function validate(mtgMetaInfo $meta) {}
-
-  function addPartial(mtgMetaParsedModule $module, mtgMetaService $service)
-  {
-    $this->setTokens(array_merge($this->getTokens(), $service->getTokens()));
-    $this->parent_scope->addScope($service->getParentScope());
-    $this->partials[$module->file] = $service;
-  }
-
-  function getPartials() : array
-  {
-    return $this->partials;
-  }
-
-  function getName() : string
-  {
-    return $this->name;
-  }
-
-  function getMetaId()
-  {
-    return $this->name;
-  }
-
-  function findSymbol(string $name) : ?mtgMetaUnit
-  {
-    if(isset($this->user_types[$name]))
-      return $this->user_types[$name];
-
-    return $this->parent_scope->findSymbol($name);
-  }
-
-  function getRPCs() : array
-  {
-    return $this->rpcs;
-  }
-
-  function addRPC(mtgMetaRPC $rpc)
-  {
-    foreach($this->rpcs as $name => $_rpc)
-    {
-      if($name == $rpc->getName())
-        throw new Exception("Service '{$this->name}' already has RPC '{$rpc->getName()}'");
-
-      if($rpc->getNumericCode() == $_rpc->getNumericCode())
-        throw new Exception("Service '{$this->name}' already has RPC '{$_rpc->getName()}' with code '{$rpc->getNumericCode()}'");
-    }
-
-    $this->rpcs[$rpc->getName()] = $rpc;
-  }
-
-  function hasRPC(string $name) : bool
-  {
-    return isset($this->rpcs[$name]);
-  }
-
-  function getRPC(string $name) : mtgMetaRPC
-  {
-    if(!isset($this->rpcs[$name]))
-      throw new Exception("No such RPC '$name'");
-    return $this->rpcs[$name];
-  }
-
-  function getUserTypes() : array
-  {
-    return $this->user_types;
-  }
-
-  function addUserType(mtgUserType $utype)
-  {
-    if($this->hasRPC($utype->getName()) || $this->hasUserType($utype->getName()))
-      throw new Exception("Service '{$this->name}' already has type '{$utype->getName()}'");
-
-    $this->user_types[$utype->getName()] = $utype;
-  }
-
-  function hasUserType(string $name) : bool
-  {
-    return isset($this->user_types[$name]);
-  }
-
-  function getUserType(bool $name) : mtgUserType
-  {
-    if(!isset($this->user_types[$name]))
-      throw new Exception("No such user type '$name'");
-    return $this->user_types[$name];
-  }
-
-  function addEvent(mtgMetaStruct $evt)
-  {
-    $this->events[] = $evt;
-    $this->addUserType($evt);
-  }
-
-  function getEvents() : array
-  {
-    return $this->events;
-  }
-
-  function getClassId() : int
-  {
-    if($this->hasToken('class_id'))
-      return $this->getToken('class_id');
-
-    return crc32($this->name);
-  }
-
-  function __toString()
-  {
-    return $this->name;
-  }
-}
-
-class mtgBuiltinType implements mtgType
-{
-  private $name;
-
-  function __construct($name)
-  {
-    if(!in_array($name, mtgMetaInfo::$BUILTIN_TYPES))
-      throw new Exception("Not a built-in type '$name'");
-
-    $this->name = $name;
-  }
-
-  function getName()
-  {
-    return $this->name;
-  }
-
-  function __toString()
-  {
-    return $this->name;
-  }
-
-  function isNumeric()
-  {
-    return !$this->isString() && !$this->isBool() && !$this->isBlob();
-  }
-
-  function isString()
-  {
-    return $this->name === 'string';
-  }
-
-  function isInt()
-  {
-    return strpos($this->name, 'int') === 0;
-  }
-
-  function isUint()
-  {
-    return strpos($this->name, 'uint') === 0;
-  }
-
-  function isUint8()
-  {
-    return $this->name === 'uint8';
-  }
-
-  function isUint16()
-  {
-    return $this->name === 'uint16';
-  }
-
-  function isUint32()
-  {
-    return $this->name === 'uint32';
-  }
-
-  function isUint64()
-  {
-    return $this->name === 'uint64';
-  }
-
-  function isInt64()
-  {
-    return $this->name === 'int64';
-  }
-
-  function isInt8()
-  {
-    return $this->name === 'int8';
-  }
-
-  function isInt16()
-  {
-    return $this->name === 'int16';
-  }
-
-  function isInt32()
-  {
-    return $this->name === 'int32';
-  }
-
-  function isFloat()
-  {
-    return $this->name === 'float';
-  }
-
-  function isDouble()
-  {
-    return $this->name === 'double';
-  }
-
-  function isBool()
-  {
-    return $this->name === 'bool';
-  }
-
-  function isBlob()
-  {
-    return $this->name === 'blob';
-  }
-}
-
-class mtgMultiType implements mtgType
-{
-  private $values = array();
-
-  function __construct(array $values = array())
-  {
-    foreach($values as $v)
-      $this->addValue($v);
-  }
-
-  function addValue(mtgTypeRef $val)
-  {
-    $this->values[] = $val;
-  }
-
-  function getValues()
-  {
-    $vals = array();
-    foreach($this->values as $val)
-      $vals[] = $val->resolve();
-
-    return $vals;
-  }
-
-  function getName()
-  {
-    $str = '';
-    foreach($this->getValues() as $val)
-      $str .= $val . ';';
-    return $str;
-  }
-
-  function __toString()
-  {
-    return $this->getName();
-  }
-}
-
-class mtgArrType implements mtgType
-{
-  private $value;
-
-  function __construct(mtgTypeRef $value)
-  {
-    $this->value = $value;
-  }
-
-  function getName()
-  {
-    return $this->getValue() . '[]';
-  }
-
-  function __toString()
-  {
-    return $this->getName();
-  }
-
-  function getValue()
-  {
-    return $this->value->resolve();
-  }
-}
-
-class mtgMetaField
-{
-  private $name;
-  private $type;
-  private $tokens = array();
-
-  function __construct($name, mtgTypeRef $type)
-  {
-    $this->name = $name;
-    $this->type = $type;
-  }
-
-  function setName($name)
-  {
-    $this->name = $name;
-  }
-
-  function getName()
-  {
-    return $this->name;
-  }
-
-  function getType()
-  {
-    return $this->type->resolve();
-  }
-
-  function getTokens()
-  {
-    return $this->tokens;
-  }
-
-  function setTokens(array $tokens)
-  {
-    $this->tokens = $tokens;
-  }
-
-  function setToken($name, $val)
-  {
-    $this->tokens[$name] = $val;
-  }
-
-  function hasToken($name)
-  {
-    return array_key_exists($name, $this->tokens);
-  }
-
-  function getToken($name)
-  {
-    return $this->hasToken($name) ? $this->tokens[$name] : null; 
-  }
-  
-}
-
-class mtgMetaPacket extends mtgMetaStruct
-{
-  private $code;
-
-  function __construct($code, $name, array $tokens = array())
-  {
-    $this->code = $code;
-
-    parent::__construct($name, array(), null, $tokens);
-  }
-
-  function getPrefix()
-  {
-    list($prefix,) = explode('_', $this->getName());
-    return $prefix;
-  }
-
-  function getFullName()
-  {
-    return $this->code . "_" . $this->getName();
-  }
-
-  function getCode()
-  {
-    return $this->code;
-  }
-
-  function getNumericCode()
-  {
-    return (int)$this->code;
-  }
-}
-
-class mtgMetaEnum extends mtgUserType
-{
-  private $values = array();
-
-  function validate(mtgMetaInfo $meta) {}
-
-  function addValue($value_name, $value)
-  {
-    if(isset($this->values[$value_name]))
-      throw new Exception("Enum '{$this->name}' already has value with name '{$value_name}'");
-
-    if(in_array($value, $this->values))
-      throw new Exception("Enum '{$this->name}' already has value '{$value}'");
-
-    $this->values[$value_name] = $value; 
-  }
-
-  function calcOrValue($or_keys)
-  {
-    $res = 0;
-    foreach($or_keys as $value_name)
-    {
-      if(!isset($this->values[$value_name]))
-        throw new Exception("Enum '{$this->name}' has no value '{$value_name}'");
-      $res |= $this->values[$value_name];
-    }
-
-    return $res;
-  }
-
-  function addOrValues($values)
-  {
-    foreach($values as $value_name => $or_keys)
-      $this->addValue($value_name, $this->calcOrValue($or_keys));
-  }
-
-  function getValues()
-  {
-    return $this->values;
-  }
-
-  function override(mtgMetaEnum $other)
-  {
-    $this->tokens = array_merge($this->tokens, $other->getTokens());
-    $this->values = array_merge($this->values, $other->getValues());
-  }
-
-  function replace(mtgMetaEnum $other)
-  {
-    $this->tokens = $other->getTokens();
-    $this->values = $other->getValues();
-  }
-} 
-
-function mtg_get_all_fields(mtgMetaStruct $struct)
-{
-  $fields = $struct->getFields();
-  $parent = $struct->getParent();
-  if($parent)
-    //NOTE: order is important, parent fields must come first
-    $fields = array_merge(mtg_get_all_fields($parent), $fields);
-  return $fields;
-}
-
-function mtg_find_field_owner(mtgMetaStruct $struct, $name) 
-{
-  $tmp = $struct;
-  while($tmp)
-  {
-    $fields = $tmp->getFields();
-    if(isset($fields[$name]))
-      return $tmp;
-    $tmp = $tmp->getParent();
-  }
-  return null;
-}
-
-function mtg_try_get_token_in_hierarchy(mtgMetaStruct $struct, $name, &$value)
-{
-  $tmp = $struct;
-  while($tmp)
-  {
-    if($tmp->hasToken($name))
-    {
-      $value = $tmp->getToken($name);
-      return true;
-    }
-    $tmp = $tmp->getParent();
-  }
-
-  return false;
-}
diff --git a/parser.inc.php b/parser.inc.php
index 14d5dcf..578147b 100644
--- a/parser.inc.php
+++ b/parser.inc.php
@@ -23,7 +23,7 @@ class mtgMetaParsedModule implements mtgScope
 
   function addUnit(mtgMetaInfoUnit $unit)
   {
-    $this->units[$unit->object->getMetaId()] = $unit;
+    $this->units[$unit->object->getName()] = $unit;
   }
 
   function findSymbol(string $name) : ?mtgMetaUnit
@@ -54,7 +54,13 @@ class mtgMetaParsedModule implements mtgScope
   }
 }
 
-function mtg_parse_meta(array $meta_srcs, $valid_tokens = null, $inc_path = null, $version = null, string $extension = '.meta')
+function mtg_parse_meta(
+  array $meta_srcs, 
+  $valid_tokens = null, 
+  $inc_path = null, 
+  $version = null, 
+  string $extension = '.meta'
+) : mtgMetaInfo
 {
   if($inc_path === null)
   {
@@ -122,7 +128,7 @@ function mtg_resolve_files(string $dir_or_file, string $extension = '.meta') : a
   return $files;
 }
 
-function mtg_find_meta_files($dir, $extension = '.meta')
+function mtg_find_meta_files($dir, $extension = '.meta') : array
 {
   $items = scandir($dir);
   if($items === false)
diff --git a/parser1.inc.php b/parser1.inc.php
index e363e3e..084c6b0 100644
--- a/parser1.inc.php
+++ b/parser1.inc.php
@@ -359,7 +359,7 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
     return $values;
   }
 
-  private function _parseEnum($is_global = true) : mtgMetaEnum
+  private function _parseEnum(bool $is_global = true) : mtgMetaEnum
   {
     $this->_nextT();
     $name = $this->_parseDotName();
@@ -398,7 +398,7 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
       if(!$is_global)
         $this->_error("Override supported for global enums only");
 
-      $existing = $this->current_meta->findUnit($enum->getMetaId());
+      $existing = $this->current_meta->findUnit($enum->getName());
       if(!$existing)
         $this->_error("Not found '{$name}' enum to override values");
       if(!($existing->object instanceof mtgMetaEnum))
@@ -413,7 +413,7 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
       if(!$is_global)
         $this->_error("Replace supported for global enums only");
 
-      $existing = $this->current_meta->findUnit($enum->getMetaId());
+      $existing = $this->current_meta->findUnit($enum->getName());
       if(!$existing)
         $this->_error("Not found '{$name}' enum to replace values");
       if(!($existing->object instanceof mtgMetaEnum))
@@ -564,6 +564,7 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
 
   private function _addUnit(mtgMetaInfoUnit $unit)
   {
+    $unit->object->setScope($this->_scope());
     $this->current_meta->addUnit($unit);
     $this->module->addUnit($unit);
   }
@@ -576,7 +577,7 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
     $this->_addUnit(new mtgMetaInfoUnit($this->module, $fn));
   }
 
-  private function _parseStruct($is_global = true) : mtgMetaStruct
+  private function _parseStruct(bool $is_global = true) : mtgMetaStruct
   {
     $this->_nextT();
     $struct_origin = new mtgOrigin($this->file, $this->line);
@@ -664,7 +665,7 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
       $this->_nextT();
   }
 
-  private function _parseRPC($is_global = true) : mtgMetaRPC
+  private function _parseRPC(bool $is_global = true) : mtgMetaRPC
   {
     $this->_nextT();
     $code = $this->T_value;
@@ -683,12 +684,12 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
       { return $this->_nextIf(self::T_End); } 
     );
 
-    $req = new mtgMetaPacket($code, $is_global ? "RPC_REQ_$name" : "Request");
+    $req = new mtgMetaPacket(intval($code), $is_global ? "RPC_REQ_$name" : "Request");
     $req->setFields($req_fields);
-    $rsp = new mtgMetaPacket($code, $is_global ? "RPC_RSP_$name" : "Response");
+    $rsp = new mtgMetaPacket(intval($code), $is_global ? "RPC_RSP_$name" : "Response");
     $rsp->setFields($rsp_fields);
 
-    $rpc = new mtgMetaRPC($is_global ? "RPC_$name" : $name, $code, $req, $rsp, $tokens);
+    $rpc = new mtgMetaRPC($is_global ? "RPC_$name" : $name, intval($code), $req, $rsp, $tokens);
 
     if($is_global)
       $this->_addUnit(new mtgMetaInfoUnit($this->module, $rpc));
@@ -712,7 +713,7 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
     $existing = null;
     if($service->hasToken('service_partial'))
     {
-      $existing = $this->current_meta->findUnit($service->getMetaId());
+      $existing = $this->current_meta->findUnit($service->getName());
       if($existing)
       {
         if(!($existing->object instanceof mtgMetaService))
@@ -734,11 +735,11 @@ class mtgMetaInfoParser implements mtgIMetaInfoParser
         break;
       $key = $this->T_value;
       if($this->T == self::T_RPC)
-        $service->addRPC($this->_parseRPC(false));
+        $service->addRPC($this->_parseRPC(is_global: false));
       else if($this->T == self::T_Enum)
-        $service->addUserType($this->_parseEnum(false));
+        $service->addUserType($this->_parseEnum(is_global: false));
       else if($this->T == self::T_Struct)
-        $service->addUserType($this->_parseStruct(false));
+        $service->addUserType($this->_parseStruct(is_global: false));
       else
         $this->_error("Unsupported type");
     }
diff --git a/parser2.inc.php b/parser2.inc.php
index 5ccf2a4..8200f8a 100644
--- a/parser2.inc.php
+++ b/parser2.inc.php
@@ -359,7 +359,7 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
     return $values;
   }
 
-  private function _parseEnum($is_global = true) : mtgMetaEnum
+  private function _parseEnum(bool $is_global = true) : mtgMetaEnum
   {
     $this->_nextT();
     $name = $this->_parseDotName();
@@ -400,7 +400,7 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
       if(!$is_global)
         $this->_error("Override supported for global enums only");
 
-      $existing = $this->current_meta->findUnit($enum->getMetaId());
+      $existing = $this->current_meta->findUnit($enum->getName());
       if(!$existing)
         $this->_error("Not found '{$name}' enum to override values");
       if(!($existing->object instanceof mtgMetaEnum))
@@ -415,7 +415,7 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
       if(!$is_global)
         $this->_error("Replace supported for global enums only");
 
-      $existing = $this->current_meta->findUnit($enum->getMetaId());
+      $existing = $this->current_meta->findUnit($enum->getName());
       if(!$existing)
         $this->_error("Not found '{$name}' enum to replace values");
       if(!($existing->object instanceof mtgMetaEnum))
@@ -566,6 +566,7 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
 
   private function _addUnit(mtgMetaInfoUnit $unit)
   {
+    $unit->object->setScope($this->_scope());
     $this->current_meta->addUnit($unit);
     $this->module->addUnit($unit);
   }
@@ -609,7 +610,7 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
     return $s;
   }
 
-  private function _parseStruct()
+  private function _parseStruct(bool $is_global = true) : mtgMetaStruct
   {
     $this->_nextT();
     $struct_origin = new mtgOrigin($this->file, $this->line);
@@ -640,7 +641,9 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
 
     $s = new mtgMetaStruct($name, array(), $parent, array(), $implements);
     $s->setOrigin($struct_origin);
-    $this->_addUnit(new mtgMetaInfoUnit($this->module, $s));
+
+    if($is_global)
+      $this->_addUnit(new mtgMetaInfoUnit($this->module, $s));
 
     $tokens = $this->shared_tokens;
     if($this->T == self::T_Prop)
@@ -669,6 +672,8 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
       foreach($funcs as $fn)
         $s->addFunc($fn);
     }
+
+    return $s;
   }
 
   private function _parseInterface()
@@ -695,7 +700,7 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
       $this->_nextT();
   }
 
-  private function _parseRPC($is_global = true) : mtgMetaRPC
+  private function _parseRPC(bool $is_global = true) : mtgMetaRPC
   {
     $this->_nextT();
     $code = $this->T_value;
@@ -717,12 +722,12 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
       { return $this->_nextIf(ord('}')); } 
     );
 
-    $req = new mtgMetaPacket($code, $is_global ? "RPC_REQ_$name" : "Request");
+    $req = new mtgMetaPacket(intval($code), $is_global ? "RPC_REQ_$name" : "Request");
     $req->setFields($req_fields);
-    $rsp = new mtgMetaPacket($code, $is_global ? "RPC_RSP_$name" : "Response");
+    $rsp = new mtgMetaPacket(intval($code), $is_global ? "RPC_RSP_$name" : "Response");
     $rsp->setFields($rsp_fields);
 
-    $rpc = new mtgMetaRPC($is_global ? "RPC_$name" : $name, $code, $req, $rsp, $tokens);
+    $rpc = new mtgMetaRPC($is_global ? "RPC_$name" : $name, intval($code), $req, $rsp, $tokens);
 
     if($is_global)
       $this->_addUnit(new mtgMetaInfoUnit($this->module, $rpc));
@@ -748,7 +753,7 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
     $existing = null;
     if($service->hasToken('service_partial'))
     {
-      $existing = $this->current_meta->findUnit($service->getMetaId());
+      $existing = $this->current_meta->findUnit($service->getName());
       if($existing)
       {
         if(!($existing->object instanceof mtgMetaService))
@@ -770,9 +775,11 @@ class mtgMetaInfoParser2 implements mtgIMetaInfoParser
         break;
       $key = $this->T_value;
       if($this->T == self::T_RPC)
-        $service->addRPC($this->_parseRPC(false));
+        $service->addRPC($this->_parseRPC(is_global: false));
       else if($this->T == self::T_Enum)
-        $service->addUserType($this->_parseEnum(false));
+        $service->addUserType($this->_parseEnum(is_global: false));
+      else if($this->T == self::T_Struct)
+        $service->addUserType($this->_parseStruct(is_global: false));
       else if($this->T == self::T_Event)
         $service->addEvent($this->_parseEvent());
       else
diff --git a/scope.inc.php b/scope.inc.php
new file mode 100644
index 0000000..f25afea
--- /dev/null
+++ b/scope.inc.php
@@ -0,0 +1,28 @@
+<?php
+
+interface mtgScope
+{
+  function findSymbol(string $name) : ?mtgMetaUnit;
+}
+
+class mtgMultiScope implements mtgScope
+{
+  private array $scopes = array();
+
+  function addScope(mtgScope $scope)
+  {
+    $this->scopes[] = $scope;
+  }
+
+  function findSymbol(string $name) : ?mtgMetaUnit
+  {
+    foreach($this->scopes as $scope)
+    {
+      $unit = $scope->findSymbol($name);
+      if($unit)
+        return $unit;
+    }
+    return null;
+  }
+}
+
diff --git a/service.inc.php b/service.inc.php
new file mode 100644
index 0000000..1802c79
--- /dev/null
+++ b/service.inc.php
@@ -0,0 +1,217 @@
+<?php
+
+class mtgMetaService extends mtgMetaUnit implements mtgScope
+{
+  private string $name;
+  //to better handle partial services, since we need to lookup in multiple scopes
+  private mtgMultiScope $merged_scope;
+  private $rpcs = array();
+  private $events = array();
+  private $user_types = array();
+  private $partials = array();
+
+  function __construct(string $name, mtgScope $scope, array $tokens = array())
+  {
+    $this->name = $name;
+    $this->merged_scope = new mtgMultiScope();
+    $this->merged_scope->addScope($scope);
+    $this->scope = $scope;
+    $this->tokens = $tokens;
+  }
+
+  function validate(mtgMetaInfo $meta) {}
+
+  function addPartial(mtgMetaParsedModule $module, mtgMetaService $service)
+  {
+    $this->setTokens(array_merge($this->getTokens(), $service->getTokens()));
+    $this->merged_scope->addScope($service->getScope());
+    $this->partials[$module->file] = $service;
+  }
+
+  function getPartials() : array
+  {
+    return $this->partials;
+  }
+
+  function getName() : string
+  {
+    return $this->name;
+  }
+
+  function findSymbol(string $name) : ?mtgMetaUnit
+  {
+    if(isset($this->user_types[$name]))
+      return $this->user_types[$name];
+
+    return $this->merged_scope->findSymbol($name);
+  }
+
+  function getRPCs() : array
+  {
+    return $this->rpcs;
+  }
+
+  function addRPC(mtgMetaRPC $rpc)
+  {
+    $rpc->setScope($this);
+
+    foreach($this->rpcs as $name => $_rpc)
+    {
+      if($name == $rpc->getName())
+        throw new Exception("Service '{$this->name}' already has RPC '{$rpc->getName()}'");
+
+      if($rpc->getNumericCode() == $_rpc->getNumericCode())
+        throw new Exception("Service '{$this->name}' already has RPC '{$_rpc->getName()}' with code '{$rpc->getNumericCode()}'");
+    }
+
+    $this->rpcs[$rpc->getName()] = $rpc;
+  }
+
+  function hasRPC(string $name) : bool
+  {
+    return isset($this->rpcs[$name]);
+  }
+
+  function getRPC(string $name) : mtgMetaRPC
+  {
+    if(!isset($this->rpcs[$name]))
+      throw new Exception("No such RPC '$name'");
+    return $this->rpcs[$name];
+  }
+
+  function getUserTypes() : array
+  {
+    return $this->user_types;
+  }
+
+  function addUserType(mtgUserType $utype)
+  {
+    $utype->setScope($this);
+
+    if($this->hasRPC($utype->getName()) || $this->hasUserType($utype->getName()))
+      throw new Exception("Service '{$this->name}' already has user type with name '{$utype->getName()}'");
+
+    $this->user_types[$utype->getName()] = $utype;
+  }
+
+  function hasUserType(string $name) : bool
+  {
+    return isset($this->user_types[$name]);
+  }
+
+  function getUserType(bool $name) : mtgUserType
+  {
+    if(!isset($this->user_types[$name]))
+      throw new Exception("No such user type '$name'");
+    return $this->user_types[$name];
+  }
+
+  function addEvent(mtgMetaStruct $evt)
+  {
+    $evt->setScope($this);
+
+    $this->events[] = $evt;
+    $this->addUserType($evt);
+  }
+
+  function getEvents() : array
+  {
+    return $this->events;
+  }
+
+  function getClassId() : int
+  {
+    if($this->hasToken('class_id'))
+      return $this->getToken('class_id');
+
+    return crc32($this->name);
+  }
+
+  function __toString()
+  {
+    return $this->name;
+  }
+}
+
+class mtgMetaRPC extends mtgMetaUnit
+{
+  private string $name;
+  private int $code;
+  private mtgMetaPacket $in;
+  private mtgMetaPacket $out;
+
+  function __construct(string $name, int $code, mtgMetaPacket $in, mtgMetaPacket $out, array $tokens = array())
+  {
+    $this->name = $name;
+    $this->code = $code;
+    $this->in = $in;
+    $this->out = $out;
+    $this->tokens = $tokens;
+  }
+
+  function validate(mtgMetaInfo $meta) {}
+
+  function getName() : string
+  {
+    return $this->name;
+  }
+
+  function getCode() : int
+  {
+    return $this->code;
+  }
+
+  // deprecated?
+  function getNumericCode() : int
+  {
+    return (int)$this->code;
+  }
+
+  function getReq() : mtgMetaPacket
+  {
+    return $this->in;
+  }
+
+  function getRsp() : mtgMetaPacket
+  {
+    return $this->out;
+  }
+}
+
+
+class mtgMetaPacket extends mtgMetaStruct
+{
+  private int $code;
+
+  function __construct(int $code, string $name, array $tokens = array())
+  {
+    $this->code = $code;
+
+    parent::__construct($name, array(), null, $tokens);
+  }
+
+  // deprecated
+  function getPrefix() : string
+  {
+    list($prefix,) = explode('_', $this->getName());
+    return $prefix;
+  }
+
+  // deprecated
+  function getFullName() : string
+  {
+    return $this->code . "_" . $this->getName();
+  }
+
+  function getCode() : int
+  {
+    return $this->code;
+  }
+
+  // deprecated
+  function getNumericCode() : int
+  {
+    return (int)$this->code;
+  }
+}
+
diff --git a/struct.inc.php b/struct.inc.php
new file mode 100644
index 0000000..0ec2b0d
--- /dev/null
+++ b/struct.inc.php
@@ -0,0 +1,232 @@
+<?php
+
+class mtgMetaStruct extends mtgUserType
+{
+  protected array $fields = array();
+  protected array $funcs = array();
+  protected ?mtgTypeRef $parent = null;
+  protected array $implements = array();
+
+  private ?int $crc_class_id = null;
+
+  function __construct(string $name, array $fields = array(), 
+    mtgTypeRef $parent = null, array $tokens = array(), 
+    array $implements = array())
+  {
+    parent::__construct($name);
+
+    $this->setFields($fields);
+    $this->parent = $parent;
+    $this->tokens = $tokens;
+    $this->implements = $implements;
+  }
+
+  function getClassId() : int
+  {
+    if($this->hasToken('class_id'))
+      return $this->getToken('class_id');
+
+    if(is_null($this->crc_class_id))
+    {
+      if($this->scope != null)
+        $this->crc_class_id = crc32($this->getFullName());
+      else
+        //TODO: migrate to crc32 from crc28
+        $this->crc_class_id = crc32($this->name) & 0xFFFFFFF;
+    }
+
+    return $this->crc_class_id;
+  }
+
+  function getFullName() : string
+  {
+    $full_name = $this->getName();
+    $scope = $this->getScope(); 
+    while($scope != null && !($scope instanceof mtgMetaParsedModule))
+    {
+      $full_name = $scope->getName() . '.' . $full_name;
+      $scope = $scope->getScope();
+    }
+    return $full_name;
+  }
+
+  function validate(mtgMetaInfo $meta)
+  {
+    $parent = $this->getParent();
+    while($parent != null)
+    {
+      foreach($this->fields as $name => $_)
+        if($parent->hasField($name))
+          throw new Exception("{$this->origin} : Parent struct '{$parent->getName()}' already has field '{$name}'");
+
+      foreach($this->funcs as $name => $_)
+        if($parent->hasFunc($name))
+          throw new Exception("{$this->origin} : Parent struct '{$parent->getName()}' already has func '{$name}'");
+
+      $parent = $parent->getParent();
+    }
+
+    $s = new SplObjectStorage();
+    foreach($this->getImplements() as $imp)
+    {
+      if(!($imp instanceof mtgMetaInterface))
+        throw new Exception("{$this->origin} : Not an interface '{$imp}'");
+
+      if($s->contains($imp))
+        throw new Exception("{$this->origin} : Duplicate interface reference '{$imp->getName()}'");
+      $s->attach($imp);
+    }
+
+    foreach($this->funcs as $func)
+    {
+      $func->validate($meta);
+    }
+  }
+
+  function getParent() : ?mtgMetaStruct
+  {
+    if(!$this->parent)
+      return null;
+    $resolved = $this->parent->resolve();
+    if(!($resolved instanceof mtgMetaStruct))
+      throw new Exception("Bad parent type");
+    return $resolved;
+  }
+
+  function getImplements() : array
+  {
+    if(!$this->implements)
+      return array();
+
+    $imps = array();
+    foreach($this->implements as $imp)
+      $imps[] = $imp->resolve();
+    return $imps;
+  }
+
+  function getFields() : array
+  {
+    return $this->fields;
+  }
+
+  function setFields(array $fields, bool $replace = false)
+  {
+    if($replace)
+      $this->fields = array();
+
+    foreach($fields as $field)
+      $this->addField($field);
+  }
+
+  function addField(mtgMetaField $field)
+  {
+    if($this->hasField($field->getName()))
+      throw new Exception("Struct '{$this->name}' already has field '{$field->getName()}'");
+
+    $this->fields[$field->getName()] = $field;
+  }
+
+  function delField(mtgMetaField $field)
+  {
+    if(isset($this->fields[$field->getName()]))
+      unset($this->fields[$field->getName()]);
+  }
+
+  function hasField(string $name) : bool
+  {
+    return isset($this->fields[$name]);
+  }
+
+  function getField(string $name) : mtgMetaField
+  {
+    if(!isset($this->fields[$name]))
+      throw new Exception("No such field '$name'");
+    return $this->fields[$name];
+  }
+
+  function getFuncs() : array
+  {
+    return $this->funcs;
+  }
+
+  function addFunc(mtgMetaFunc $fn)
+  {
+    if($this->hasFunc($fn->getName()))
+      throw new Exception("Struct '{$this->name}' already has func '{$fn->getName()}'");
+
+    $this->funcs[$fn->getName()] = $fn;
+  }
+
+  function hasFunc(string $name) : bool
+  {
+    return isset($this->funcs[$name]);
+  }
+
+  function getFunc(string $name) : mtgMetaFunc
+  {
+    if(!isset($this->funcs[$name]))
+      throw new Exception("No such funcs '$name'");
+    return $this->funcs[$name];
+  }
+
+  //TODO: doesn't belong here
+  function hasTokenInParent(string $name) : bool
+  {
+    return mtg_try_get_token_in_hierarchy($this, $name, $value);
+  }
+}
+
+class mtgMetaField
+{
+  private $name;
+  private $type;
+  private $tokens = array();
+
+  function __construct($name, mtgTypeRef $type)
+  {
+    $this->name = $name;
+    $this->type = $type;
+  }
+
+  function setName($name)
+  {
+    $this->name = $name;
+  }
+
+  function getName()
+  {
+    return $this->name;
+  }
+
+  function getType()
+  {
+    return $this->type->resolve();
+  }
+
+  function getTokens()
+  {
+    return $this->tokens;
+  }
+
+  function setTokens(array $tokens)
+  {
+    $this->tokens = $tokens;
+  }
+
+  function setToken($name, $val)
+  {
+    $this->tokens[$name] = $val;
+  }
+
+  function hasToken($name)
+  {
+    return array_key_exists($name, $this->tokens);
+  }
+
+  function getToken($name)
+  {
+    return $this->hasToken($name) ? $this->tokens[$name] : null; 
+  }
+}
+
+
diff --git a/type.inc.php b/type.inc.php
new file mode 100644
index 0000000..2972248
--- /dev/null
+++ b/type.inc.php
@@ -0,0 +1,272 @@
+<?php
+
+interface mtgType
+{
+  function getName() : string;
+  function __toString() : string;
+}
+
+class mtgTypeRef implements mtgType
+{
+  //TODO: not sure if it must be static
+  private static $unresolved = array();
+
+  private string $name;
+  private ?mtgScope $scope = null;
+  private ?mtgType $resolved = null;
+  private ?mtgOrigin $origin = null;
+
+  function __construct($name_or_resolved, mtgScope $scope = null, mtgOrigin $origin = null)
+  {
+    if(is_object($name_or_resolved))
+    {
+      if(!($name_or_resolved instanceof mtgType))
+        throw new Exception("Bad type");
+      $this->resolved = $name_or_resolved;
+    }
+    else
+    {
+      $this->name = $name_or_resolved;
+      if(!$scope)
+        throw new Exception("Scope is not set");
+
+      self::$unresolved[] = $this;
+    }
+
+    $this->scope = $scope;
+    $this->origin = $origin ?? new mtgOrigin();
+  }
+
+  function getName() : string
+  {
+    if($this->resolved)
+      return ''.$this->resolved;
+    else
+      return $this->name;
+  }
+
+  static function checkAllResolved()
+  {
+    while(sizeof(self::$unresolved) > 0)
+    {
+      $ref = array_shift(self::$unresolved);
+      $resolved = $ref->resolve();
+      if($resolved instanceof mtgMetaFunc && $resolved->getName())
+        throw new Exception("Invalid resolving of named function as type: " . $resolved->getName() . " at " . $ref->origin);
+    }
+  }
+
+  function resolve() : mtgType
+  {
+    if($this->resolved)
+      return $this->resolved;
+
+    $symb = $this->scope->findSymbol($this->name);
+    if($symb)
+    {
+      if(!($symb instanceof mtgType))
+        throw new Exception("{$this->origin} : Symbol '{$this->name}' is not type");
+      $this->resolved = $symb;
+      return $this->resolved;
+    }
+    else
+      throw new Exception("{$this->origin} : Symbol '{$this->name}' not found");
+  } 
+
+  function __toString()
+  {
+    return $this->getName();
+  }
+}
+
+abstract class mtgUserType extends mtgMetaUnit implements mtgType
+{
+  protected string $name;
+
+  function __construct(string $name)
+  {
+    $this->name = $name;
+  }
+
+  function getName() : string
+  {
+    return $this->name;
+  }
+
+  function setName(string $name)
+  {
+    $this->name = $name;
+  }
+
+  function __toString() : string
+  {
+    return $this->name;
+  }
+}
+
+class mtgBuiltinType implements mtgType
+{
+  private string $name;
+
+  function __construct(string $name)
+  {
+    if(!in_array($name, mtgMetaInfo::$BUILTIN_TYPES))
+      throw new Exception("Not a built-in type '$name'");
+
+    $this->name = $name;
+  }
+
+  function getName() : string 
+  {
+    return $this->name;
+  }
+
+  function __toString() : string
+  {
+    return $this->name;
+  }
+
+  function isNumeric() : bool
+  {
+    return !$this->isString() && !$this->isBool() && !$this->isBlob();
+  }
+
+  function isString() : bool
+  {
+    return $this->name === 'string';
+  }
+
+  function isInt() : bool
+  {
+    return strpos($this->name, 'int') === 0;
+  }
+
+  function isUint() : bool
+  {
+    return strpos($this->name, 'uint') === 0;
+  }
+
+  function isUint8() : bool
+  {
+    return $this->name === 'uint8';
+  }
+
+  function isUint16() : bool
+  {
+    return $this->name === 'uint16';
+  }
+
+  function isUint32() : bool
+  {
+    return $this->name === 'uint32';
+  }
+
+  function isUint64() : bool
+  {
+    return $this->name === 'uint64';
+  }
+
+  function isInt64() : bool
+  {
+    return $this->name === 'int64';
+  }
+
+  function isInt8() : bool
+  {
+    return $this->name === 'int8';
+  }
+
+  function isInt16() : bool
+  {
+    return $this->name === 'int16';
+  }
+
+  function isInt32() : bool
+  {
+    return $this->name === 'int32';
+  }
+
+  function isFloat() : bool
+  {
+    return $this->name === 'float';
+  }
+
+  function isDouble() : bool
+  {
+    return $this->name === 'double';
+  }
+
+  function isBool() : bool
+  {
+    return $this->name === 'bool';
+  }
+
+  function isBlob() : bool
+  {
+    return $this->name === 'blob';
+  }
+}
+
+class mtgMultiType implements mtgType
+{
+  private $values = array();
+
+  function __construct(array $values = array())
+  {
+    foreach($values as $v)
+      $this->addValue($v);
+  }
+
+  function addValue(mtgTypeRef $val)
+  {
+    $this->values[] = $val;
+  }
+
+  function getValues()
+  {
+    $vals = array();
+    foreach($this->values as $val)
+      $vals[] = $val->resolve();
+
+    return $vals;
+  }
+
+  function getName() : string
+  {
+    $str = '';
+    foreach($this->getValues() as $val)
+      $str .= $val . ';';
+    return $str;
+  }
+
+  function __toString() : string
+  {
+    return $this->getName();
+  }
+}
+
+class mtgArrType implements mtgType
+{
+  private mtgTypeRef $value;
+
+  function __construct(mtgTypeRef $value)
+  {
+    $this->value = $value;
+  }
+
+  function getName() : string
+  {
+    return $this->getValue() . '[]';
+  }
+
+  function __toString() : string
+  {
+    return $this->getName();
+  }
+
+  function getValue() : mixed
+  {
+    return $this->value->resolve();
+  }
+}
+
diff --git a/util.inc.php b/util.inc.php
new file mode 100644
index 0000000..3750018
--- /dev/null
+++ b/util.inc.php
@@ -0,0 +1,40 @@
+<?php
+
+function mtg_get_all_fields(mtgMetaStruct $struct)
+{
+  $fields = $struct->getFields();
+  $parent = $struct->getParent();
+  if($parent)
+    //NOTE: order is important, parent fields must come first
+    $fields = array_merge(mtg_get_all_fields($parent), $fields);
+  return $fields;
+}
+
+function mtg_find_field_owner(mtgMetaStruct $struct, $name) 
+{
+  $tmp = $struct;
+  while($tmp)
+  {
+    $fields = $tmp->getFields();
+    if(isset($fields[$name]))
+      return $tmp;
+    $tmp = $tmp->getParent();
+  }
+  return null;
+}
+
+function mtg_try_get_token_in_hierarchy(mtgMetaStruct $struct, $name, &$value)
+{
+  $tmp = $struct;
+  while($tmp)
+  {
+    if($tmp->hasToken($name))
+    {
+      $value = $tmp->getToken($name);
+      return true;
+    }
+    $tmp = $tmp->getParent();
+  }
+
+  return false;
+}