Re: [Boost-Users] Re: "Correct" way to return empty shared_ptr?

From: dick.bridges_at_[hidden]
Date: 2003-04-24 10:27:10

I don't understand C++ well enough to grok a compiler's interpretation of
the code, but I seems like I'm creating an extra copy for the return.  Oh
well, if the snippet seems ok, far be it from me to throw asparagus on it.
;)

Thanks for the help.

                                                                                                                                      
                      "Edward Diener"                                                                                                 
                      <eddielee_at_tropic         To:      boost-users_at_[hidden]                                                   
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                      04/23/2003 05:47                                                                                                
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dick.bridges_at_[hidden] wrote:
> What is the 'correct' way to return a NULL/empty shared_ptr?  For
> example, this works
>
> <snippet>
> shared_ptr<int> maybe_get_a_pointer()
> {
>       shared_ptr<int> p;
>       return(p);
> }
> </snippet>
>
> but seems 'klunky'.  I've clearly missed something in the
> docs/examples somewhere.  Can someone point me in the right direction?

What is klunky about it ? It seems pretty normal to me. Another other
possibility is to passed a reference to a shared_ptr<> and have your
function above fill it in with an actual pointer to int and return a bool
true if it succeeded or false if it did not. Another possibility is to use
boost::optional<>. Another one to pass back a bool,shared_ptr<> std::pair
or
boost::tuple. But I prefer the method you used originally.

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