Question:
If I have an array created like this:
MyType *array = new MyType[10]; And I want to overwrite one of the elements, do I have to delete first the old element like this:
delete &array[5]; array[5] = *(new MyType()); Or is this completely wrong and do I have to work with something like "pointers to pointers" to fix this job? If so, how please....
Thanks
Solution:1
It's an array of values, not of pointers. So you'd just do
array[5] = MyType(); This requires MyType to support the assignment operator.
Incidentally, there's rarely a need for manual array allocation like this in C++. Do away with the new and delete and use std::vector instead:
std::vector<MyType> array(10); array[5] = MyType(); Note, there's no need to delete anything.
Solution:2
No.
The individual elements of the array were not new'd, just the array itself was.
array[5] = MyType(); // note no `new` here.
Solution:3
You are declaring an array of MyTypes, not pointers to MyTypes. Because you don't new the elements in the array, you also don't delete them. Instead, just do:
array[5] = MyType(); Note that you can also use std::vector<MyType> to put your MyTypes on the heap without worrying about the nuisances of C++ arrays.
std::vector<MyType> myTypes(10); myTypes[5] = MyType();
Solution:4
You can call a destructor in-place, then use placement new.
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