Loki/Borland/static_check.h
tslettebo b5d2cd3d11 No message
git-svn-id: svn://svn.code.sf.net/p/loki-lib/code/trunk@40 7ec92016-0320-0410-acc4-a06ded1c099a
2002-08-23 07:22:07 +00:00

60 lines
2.4 KiB
C++
Raw Blame History

////////////////////////////////////////////////////////////////////////////////
// The Loki Library
// Copyright (c) 2001 by Andrei Alexandrescu
// This code accompanies the book:
// Alexandrescu, Andrei. "Modern C++ Design: Generic Programming and Design
// Patterns Applied". Copyright (c) 2001. Addison-Wesley.
// Permission to use, copy, modify, distribute and sell this software for any
// purpose is hereby granted without fee, provided that the above copyright
// notice appear in all copies and that both that copyright notice and this
// permission notice appear in supporting documentation.
// The author or Addison-Wesley Longman make no representations about the
// suitability of this software for any purpose. It is provided "as is"
// without express or implied warranty.
////////////////////////////////////////////////////////////////////////////////
// Last update: August 9, 2002
#ifndef STATIC_CHECK_INC_
#define STATIC_CHECK_INC_
namespace Loki
{
////////////////////////////////////////////////////////////////////////////////
// Helper structure for the STATIC_CHECK macro
////////////////////////////////////////////////////////////////////////////////
template<int> struct CompileTimeError;
template<> struct CompileTimeError<true> {};
}
////////////////////////////////////////////////////////////////////////////////
// macro STATIC_CHECK
// Invocation: STATIC_CHECK(expr, id)
// where:
// expr is a compile-time integral or pointer expression
// id is a C++ identifier that does not need to be defined
// If expr is zero, id will appear in a compile-time error message.
////////////////////////////////////////////////////////////////////////////////
template<bool>
struct CompileTimeChecker
{
CompileTimeChecker(...);
};
template<> struct CompileTimeChecker<false> {};
#define STATIC_CHECK(expr, msg)\
{\
class ERROR_##msg {}; \
(void)sizeof(CompileTimeChecker<(expr)>(ERROR_##msg()));\
}
////////////////////////////////////////////////////////////////////////////////
// Change log:
// March 20, 2001: add extra parens to STATIC_CHECK - it looked like a fun
// definition
// June 20, 2001: ported by Nick Thurn to gcc 2.95.3. Kudos, Nick!!!
// July 16, 2002: Ported by Terje Sletteb<65> and Pavel Vozenilek to BCC 5.6
////////////////////////////////////////////////////////////////////////////////
#endif // STATIC_CHECK_INC_