hphp/runtime/vm/type-alias.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-2014 Facebook, Inc. (http://www.facebook.com)     |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16 #ifndef incl_HPHP_VM_TYPE_ALIAS_H_
  17 #define incl_HPHP_VM_TYPE_ALIAS_H_
  18
  19 namespace HPHP {
  20
  21 //////////////////////////////////////////////////////////////////////
  22
  23 /*
  24  * This is the runtime representation of a type alias.  Type aliases
  25  * are only allowed when HipHop extensions are enabled.
  26  *
  27  * The m_kind field is KindOfObject whenever the type alias is
  28  * basically just a name.  At runtime we still might resolve this name
  29  * to another type alias, becoming a type alias for KindOfArray or
  30  * something in that request.
  31  *
  32  * For the per-request struct, see TypeAliasReq below.
  33  */
  34 struct TypeAlias {
  35   LowStringPtr name;
  36   LowStringPtr value;
  37   DataType     kind;
  38   bool         nullable; // Null is allowed; for ?Foo aliases
  39   Attr         attrs;
  40
  41   template<class SerDe> void serde(SerDe& sd) {
  42     sd(name)
  43       (value)
  44       (kind)
  45       (nullable)
  46       (attrs)
  47       ;
  48   }
  49 };
  50
  51 /*
  52  * In a given request, a defined type alias is turned into a
  53  * TypeAliasReq struct.  This contains the information needed to
  54  * validate parameter type hints for a type alias at runtime.
  55  */
  56 struct TypeAliasReq {
  57   DataType kind;      // may be KindOfAny for "HH\\mixed"
  58   bool nullable;      // for option types, like ?Foo
  59   LowClassPtr klass;  // nullptr if kind != KindOfObject
  60   LowStringPtr name;  // needed for error messages; nullptr if not defined
  61 };
  62
  63 //////////////////////////////////////////////////////////////////////
  64
  65 }
  66
  67 #endif