cast.hh

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/*
 * Copyright (c) 2008 The Hewlett-Packard Development Company
 * All rights reserved.
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 * this software without specific prior written permission.
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#ifndef __BASE_CAST_HH__
#define __BASE_CAST_HH__
 
#include <cassert>
 
// This is designed for situations where we have a pointer to a base
// type, but in all cases when we cast it to a derived type, we know
// by construction that it should work correctly.
 
#if defined(DEBUG)
 
// In debug builds, do the dynamic cast and assert the result is good
 
template <class T, class U>
inline T
safe_cast(U ptr)
{
    T ret = dynamic_cast<T>(ptr);
    assert(ret);
    return ret;
}
 
#else
 
// In non debug builds statically cast the result to the pointer we
// want to use.  This is technically unsafe, but this is only for
// cases where we know that this should work by construction.
 
template <class T, class U>
inline T
safe_cast(U ptr)
{
    return static_cast<T>(ptr);
}
 
#endif
 
#endif // __BASE_CAST_HH__