> >
> > I need a confirmation. According the standard should:
> >
> > std::vector<int> intVector(10);
> >
> > be a vector full of 0?
> >
> > I already check some topics about basic types default constructor but
> > haven't found anything about their behavior inside the STL.
>
> The values have the default value of the type, which is in this case 'int',
> and the default value for 'int' is 0, ie. int i(); sets i to 0.
>

Thanks for the answer but it made me thought about an other point. Do
pointers have default value?

Should

std::vector<int*> intPtrVector(10);

be full of null pointers?

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Francois Dumont wrote:
>>>I need a confirmation. According the standard should:
>>>
>>>std::vector<int> intVector(10);
>>>
>>>be a vector full of 0?
>>>
>>>I already check some topics about basic types default constructor but
>>>haven't found anything about their behavior inside the STL.
>>
>>The values have the default value of the type, which is in this case 'int',
>>and the default value for 'int' is 0, ie. int i(); sets i to 0.
>>
>
>
> Thanks for the answer but it made me thought about an other point. Do
> pointers have default value?
>
> Should
>
> std::vector<int*> intPtrVector(10);
>
> be full of null pointers?

Yes, but note that this question would be more appropriate
for comp.lang.c++.moderated.  Followups set accordingly.

The declaration of intPtrVector above is roughly equivalent to

typedef int* ptr_to_int;
std::vector<int*> intPtrVector(10, ptr_to_int());

and ptr_to_int() gives a null pointer.  As a technicality,
the elements of the container are copy constructed from the
one default constructed argument (whether explicitly
supplied or from the default argument), rather than being
default constructed themselves.

-- James.

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>
> std::vector<int*> intPtrVector(10);
>
> be full of null pointers?

I am not sure but the standard in 8.5 paragraph 5 says:

To zero-initialize storage for an object of type T means:
- if T is scalar type (3.9), the storage is set to the value of 0 (zero)
converted to T.

In 3.9 I can see that int* is a scalar type.

As I understand the standard the answer to your question IMHO should be yes.
I should do some tests with some compilers to really check this.

Romulus




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