Cast.h

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/*
 * Copyright(c) Sophist Solutions, Inc. 1990-2025.  All rights reserved
 */
#ifndef _Stroika_Foundation_Debug_Cast_h_
#define _Stroika_Foundation_Debug_Cast_h_ 1
 
#include "Stroika/Foundation/StroikaPreComp.h"
 
#include <memory>
 
#include "Stroika/Foundation/Debug/Assertions.h"
 
/**
 *  \file
 *
 */
 
namespace Stroika::Foundation::Debug {
 
    /**
     *  \brief return the same value as dynamic_cast<T> would have, except instead of checking nullptr,
     *         only check in DEBUG builds, and there ASSERT != null (if original pointer not null)
     * 
     *  \pre arg != nullptr
     *
     *  Use where you would want to check Assert (dynamic_cast<const T*> (&ir) != nullptr) and then do static_cast<> instead;)
     * 
     *      AssertMember (&ir, IteratorRep_);
     *      auto&   mir = static_cast<const IteratorRep_&> (ir);
     * 
     *  The purpose of this function is to gain the performance of static_cast<> but the safety / checking of dynamic_cast (in debug builds).
     * 
     *  \par Example Usage
     *      \code
     *          auto&   mir = Debug::UncheckedDynamicCast<const IteratorRep_&> (i.ConstGetRep ());
     *      \endcode
     * 
     * 
     *  \par Example Usage
     *      \code
     *              virtual bool Equals (const IRep* rhs) const override
     *              {
     *                  RequireNotNull (rhs);
     *                  RequireMember (rhs, MyIterRep_);
     *                  const MyIterRep_* rrhs = Debug::UncheckedDynamicCast<const MyIterRep_*> (rhs);
     *                  return fData_.data () == rrhs->fData_.data () and fIdx_ == rrhs->fIdx_;
     *              }
     *      \endcode
     *              
     *  \see https://stackoverflow.com/questions/28002/regular-cast-vs-static-cast-vs-dynamic-cast
     * 
     *  \note this does NOT work (should be checked somehow/assert/type info @todo) - with virtual inheritance.
     */
    template <typename T, typename T1>
    T UncheckedDynamicCast (T1&& arg) noexcept;
 
    /**
     *  \brief Produce the same result as dynamic_pointer_cast if the successful case (non-null) - with better performance.
     * 
     *  \pre arg != nullptr
     *  \pre dynamic_pointer_cast<T> (arg) != nullptr
     * 
     *  \see UncheckedDynamicCast and dynamic_pointer_cast
     * 
     *  @todo CONSIDER USING SAME NAME - UncheckedDynamicCast - and overload. Done this way cuz std c++ does it that way, but not sure thats a good reason here.
     */
    template <typename T, typename T1>
    std::shared_ptr<T> UncheckedDynamicPointerCast (const std::shared_ptr<T1>& arg) noexcept;
 
}
 
/*
 ********************************************************************************
 ***************************** Implementation Details ***************************
 ********************************************************************************
 */
#include "Cast.inl"
 
#endif /*_Stroika_Foundation_Debug_Cast_h_*/