In neither case can you initialize the elements of your array using the 'new'
syntax.

Devaki Parikh wrote:

> Hi! All,
>     Could someone please tell me about the c++ standard for dynamically
> allocating arrays ? Are the following statements valid ?
>
> int **p1, *p2;
>
> p1 = new (int*) [10] (0);
> // would the above line of code generate array of ten pointers to
> integers and initialize // them to NULL ?
>
> p2 = new int [10] (5);
> // would the above line of code generate an array of ten integers all
> initialized to 5 ?
---
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Devaki Parikh wrote:

>    Could someone please tell me about the c++ standard for dynamically
> allocating arrays ? Are the following statements valid ?

> int **p1, *p2;

> p1 = new (int*) [10] (0);
> // would the above line of code generate array of ten pointers to
> integers and initialize // them to NULL ?

> p2 = new int [10] (5);
> // would the above line of code generate an array of ten integers all
> initialized to 5 ?

Nope. operator new[] can only use a default constructor for the objects
in the array, and the default constructor for built-in types is empty,
meaning that the values are undefined. You're not the first person to
wish it were otherwise.

--

Ciao,
Paul


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Hi! All,
    Could someone please tell me about the c++ standard for dynamically
allocating arrays ? Are the following statements valid ?

int **p1, *p2;

p1 = new (int*) [10] (0);
// would the above line of code generate array of ten pointers to
integers and initialize // them to NULL ?

p2 = new int [10] (5);
// would the above line of code generate an array of ten integers all
initialized to 5 ?

Thanks
Devaki
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