Disallow arrays as pointers

[deadalnix]

Le 31/10/2011 21:25, Timon Gehr a écrit :
> On 10/31/2011 08:34 PM, bearophile wrote:
>> I don't see the need to accept this cast, because we have said that D
>> arrays are not pointers, and allowing the array to pointer cast means
>> introducing/leaving an useless special case, and in practice this
>> special case is not useful because arrays have the ptr property:
>>
>
> extern(C) void foo(char* str);
> foo(cast(char*)"hello");
>
>
>>
>> struct Foo {
>> int* p;
>> size_t n;
>> }
>> void main() {
>> Foo f;
>> auto x = f.ptr; // OK
>> }
>>
>
> Actually compile error :o).
>
>>
>> So I think cast(int*)a1 should be forbidden.
>
> -1. I don't really see any point in disallowing it. It is an explicit
> cast, not some kind of bug prone implicit behaviour.
>

Well, because the ptr property is done for that. Actually, D ABI says 
that the struct representing the array begins with length, then prt, so 
the result isn't obvious from a low level perspective, which is kinda 
sad when it goes to pointer manipulation.