Hi all,
I recently came across the following code:
// some data
struct Data { // ... some data };
// a list to hold the data
vector<Data> dataList;
// a function to erase an element inside the datalist
void destroyDataAtIn dex(int index)
{
dataList.erase( &dataList[index] ); //(a)
}
Is line (a) valid? If so, how does that work since the function
declaration of erase is erase(iterator iter)? Does it automatically
converts the address of the element to an iterator? or it makes the
assumption that an iterator is a typedef of pointer?
Also, I created a toy program with the above code snipplet, from the
test runs, some times the program will crashed. Is it because of the
way we used erase in (a)?
Thanks,
Kaede 1 4098
On 22 Nov 2003 21:16:45 -0800, ka************@ hotmail.com (kaede) wrote: Hi all,
I recently came across the following code:
// some data struct Data { // ... some data };
// a list to hold the data vector<Data> dataList;
// a function to erase an element inside the datalist void destroyDataAtIn dex(int index) { dataList.erase( &dataList[index] ); //(a) }
Is line (a) valid? If so, how does that work since the function declaration of erase is erase(iterator iter)? Does it automatically converts the address of the element to an iterator? or it makes the assumption that an iterator is a typedef of pointer?
No, it's not valid. However, it might work on some compilers that use
pointers as iterators for vectors. It will fail on others.
--
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