🚀 go-pugleaf

claus@faerber.muc.de (Claus A. Faerber) writes:

>David Sachs <b91926@fsgi01.fnal.gov> (07 Mar 96):
>
>> Should delete or delete[] be used for a pointer to an array type?
>>
>> // It is assumed that some_type is an existing type
>> typedef some_type array_type[10];
>>
>> array_type* a1 = new array_type[5];
>> array_type* b1 = new some_type[5][10];
>
>In both cases, you're creating a some_type[5][10], which is  
>an array_type[5] by typedef.

The fact that a typedef is used is irrelevant.

>It is an array of array_types, sou you have to use delete[].

Correct, because it is an array, you have to use `delete[]'.

>> array_type* a2 = new array_type;
>> array_type* b2 = new some_type[10];
>
>Here, you are creating a some_type[10] in both cases, which  
>is array_type.
>It is one single array_type, not an array of array_types, so  
>you have to use delete without [] in both cases.

No, that's incorrect.  It is, as you say, "one single array_type", but
`array_type' is an array type, so `delete[]' must be used.
See 5.3.5[expr.delete]/2.

>> delete   a2; // or should it be delete[] a2;
>
>Ok, points to a single array_type.

No, that's incorrect, for the same reason as above.

>> delete[] b2; // or should it be delete   b2;
>
>*No*, points also to a single array_type, so you actually  
>have to use delete b2.

Again, that's incorrect, for the same reason as above.

--
Fergus Henderson             	WWW: http://www.cs.mu.oz.au/~fjh
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