shared source/vb/language/shared/templateutil.h

   1 //-------------------------------------------------------------------------------------------------
   2 //
   3 //  Copyright (c) Microsoft Corporation.  All rights reserved.
   4 //
   5 // Template Utilities
   6 //
   7 //-------------------------------------------------------------------------------------------------
   8
   9 #pragma once
  10
  11 class TemplateUtil
  12 {
  13 public:
  14     template <class T>
  15     static
  16     void Swap(_Inout_ T **left, _Inout_ T **right) throw()
  17     {
  18         T *temp = *right;
  19         *right = *left;
  20         *left = temp;
  21     }
  22
  23     //-------------------------------------------------------------------------------------------------
  24     //
  25     // Useful CompileTime function that will allow you to assert an inheritance relationship between
  26     // two types.  Very helpful in certain template sceanrios.
  27     //
  28     // Use a static cast here because it will prevent operator consideration.
  29     //
  30     //-------------------------------------------------------------------------------------------------
  31     template <typename Parent, typename Child>
  32     static
  33     void CompileAssertIsChildOf()
  34     {
  35 #if DEBUG
  36         Parent *pParent = NULL;
  37         Child *pChild = NULL;
  38         pParent = static_cast<Parent*>(pChild);
  39 #endif
  40     }
  41
  42     //-------------------------------------------------------------------------------------------------
  43     //
  44     // Several of our hashing algorithms require the size of a key be a multiple of the size of
  45     // a pointer.  This function will prevent a compilation in DEBUG mode unless this is satisifed
  46     //
  47     //-------------------------------------------------------------------------------------------------
  48     template <typename T>
  49     static
  50     void CompileAssertSizeIsPointerMultiple()
  51     {
  52 #if DEBUG
  53         COMPILE_ASSERT(0 == (sizeof(T) % sizeof(void*)));
  54 #endif
  55     }
  56
  57 };
  58