Re: Scope vs. point of construction for an object

From:
annamalai <annamalai.gurusami@gmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Fri, 24 Oct 2008 16:32:00 CST
Message-ID:
<27030732-a857-4a4a-a2ab-5efa7d1e0227@e2g2000hsh.googlegroups.com>
On Oct 22, 10:59 pm, Alan McKenney <alan_mckenn...@yahoo.com> wrote:

The obvious approach -- use a pointer and "new" -- seems sort of ugly:

     T *t_ptr = 0;

     try { t_ptr = new T( /* long complicated list of constructor
arguments */ ); } catch (...) { /* stuff */ }

     // use t_ptr

     delete t_ptr; // don't forget to delete it

Is there a way that keeps the non-pointer syntax?
Even better would be if I could put it into an object.


Will something like this work?

#include <iostream>
#include <memory>

struct T
{
     T() { throw 10; }
     void pass() { std::cout << "T::pass()" << std::endl; }
};

void test1()
{
     std::auto_ptr<T> t;
     try {
         std::auto_ptr<T> __t( new T());
         t = __t;
     }
     catch ( ... )
     {}
     T* t_ptr = t.get();
     if (t_ptr) {
         T& obj = *t_ptr;
         obj.pass(); // non-pointer syntax
     }
}

int main()
{
     test1();
     return 0;
}

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