Assigning One Array To Another by reference

[TheKid]

Hello,
I'm trying to set up multiple "pointers" to the same dynamic array, but can't seem to figure out how.
reading the MS Article on how to do this on http://msdn.microsoft.com/en-us/libr...ffice.10).aspx
I was expecting to be able to change a(1) by changing b(1) on the below code snippet, but can't seem to get it to work
The statement b=a seems to make an independent copy of a, rather than make b point to the same memory location of a
This becomes apparent when the statement b(1)=.222 changes b but not a as per the "Watches" window

Any ideas on how to set more than one pointer to the same dynamic array?
Help would be much appreciated, thanks.

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[OnErrorGoto0]

I'm intrigued - why would you want this?

[TheKid]

I've got a tight loop where a functor needs to operate on an array which needs to be allocated and managed elsewhere.
The functor needs to know the array, but it cannot receive it on an argument list in every call in the loop or the loop will be significantly slower.
The standard solution is to construct the functor outside the loop passing this array as an argument so it has knowledge of it and can operate on it within the loop when it is called later.

[OnErrorGoto0]

Other than a public variable, I don't know how you could do that in VBA. VarPtr won't work with an entire array, and I'm not sure I would recommend messing about with CopyMemory API calls anyway.

[TheKid]

Interesting, but what about the MS article?
It is clearly wrong in its implementation instructions, but is it also wrong about this sort of thing even being possible?
There's gotta be a syntax for this, it's pretty basic stuff no?

[StephenR]

I don't think that article implies what you think it implies.

[OnErrorGoto0]

I don't think this is basic stuff - I can't say I have ever had a need for it that could not be achieved by simply passing the array to a function, or using a public variable.

[TheKid]

From the Microsoft article:

Assigning one array to another of the same type is quick because the first array is simply pointed to the memory location that stores the second array.

Does this not mean that Microsoft think you can look at the same array using different "pointers"?

[StephenR]

It's somewhat ambiguous, but the way I read it, it is referring only to initialising the second array. It doesn't mean any sort of subsequent connection. But, as OEG0 says, there are other ways to skin this cat.

[OnErrorGoto0]

I think it's completely misleading and couldn't be more badly worded without a lot of effort.