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Re: static_cast, cast operator, and constructors.

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On 07/19/11 11:44 AM, Noah Roberts wrote:
> On 7/18/2011 4:29 PM, Ian Collins wrote:
>> On 07/19/11 10:46 AM, Noah Roberts wrote:
>>> Considder:
>>>
>>> struct ObjectA
>>> {
>>> ObjectA(ObjectA const&);
>>>
>>> template<  typename T>
>>> ObjectA(T const&);
>>>
>>> void fun() const;
>>> };
>>>
>>> struct ObjectB
>>> {
>>> operator ObjectA () const;
>>> };
>>>
>>> static_cast<ObjectA>(an_object_b).fun();
>>>
>>> Which constructor does the standard specify will be called during the
>>> static_cast: copy or template?
>>
>> Is the code complete? The only option is the template.
>
> No, there's a second option: apply the cast operator and call the copy
> operator with the result.

Your terminology is a little confused.  There is a conversion (not cast) 
operator and a copy constructor (not operator).

The sequence you describe required two levels of conversion, the 
template constructor one.

Assignment or omitting the template constructor should call the 
conversion operator:

ObjectA a = an_object_b;

-- 
Ian Collins

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Thread

static_cast, cast operator, and constructors. Noah Roberts <dont@email.me> - 2011-07-18 15:46 -0700
  Re: static_cast, cast operator, and constructors. Ian Collins <ian-news@hotmail.com> - 2011-07-19 11:29 +1200
    Re: static_cast, cast operator, and constructors. Noah Roberts <dont@email.me> - 2011-07-18 16:44 -0700
      Re: static_cast, cast operator, and constructors. Ian Collins <ian-news@hotmail.com> - 2011-07-19 11:57 +1200
        Re: static_cast, cast operator, and constructors. Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-07-19 13:12 +0000
          Re: static_cast, cast operator, and constructors. Noah Roberts <dont@email.me> - 2011-07-19 09:26 -0700
            Re: static_cast, cast operator, and constructors. Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-07-20 18:52 +0000
  Re: static_cast, cast operator, and constructors. James Kanze <james.kanze@gmail.com> - 2011-07-20 12:53 -0700

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