Re: reallocate element in array of pointers with new and delete.

From:
Ulrich Eckhardt <eckhardt@satorlaser.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Fri, 16 Oct 2009 03:26:44 CST
Message-ID:
<k4hlq6-8m5.ln1@satorlaser.homedns.org>
Matteo wrote:

I have an array of pointers to objects in my code:

T** arr = new T*[n]


Why don't you use a std::vector<T*>? Alternatively, there are container
classes adapted for work with pointers to polymorphic objects, take a look
at e.g. Boost. BTW: Unless you have a good reason, using pointers at all is
a bad idea.

for (int i = 0; i < n; i++) arr[i] = new T;


Keep in mind that 'new' might throw bad_alloc!

De-allocating memory with a delete loop and delete[] at the end works
fine, but now I want to change the elements in the array with:

for (i = 0...)
delete arr[i];
arr[i] = new T; //crash

This version crashes,


No it doesn't. Seriously, the code you have shown doesn't cause any crash.
What you haven't shown is the real code and the real fault that happens.

Uli

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