nsCOMArray<T> and nsIArray now available

I just checked in changes that turn on nsCOMArray<T> and nsIArray.

These two classes REPLACE nsISupportsArray - no new code should be using 
nsISupportsArray! In addition, nsIArray is a public interface that will 
be frozen for embeddors.

(Reviewers, please keep this in mind when reviewing new code)

I'll be working on documentation this week, but I thought I'd give you a 
preview.

nsCOMArray<T>
-------------
similar to nsCOMPtr, this is a typed array of objects. For instance, you 
can have an array nsCOMArray<nsIContent> contentObjects which is an 
array of nsIContent* objects. This allows you to avoid calling 
QueryInterface/QueryElementAt. nsCOMArray<T> is not refcounted, and not 
scriptable. Beneath the covers, it is more or less a wrapper around 
nsVoidArray. Its elements ARE refcounted, and the strong typing will 
make it very easy to use.

Sample usage:
    // member variable
    nsCOMArray<nsIObserver> mObserverList;
...
    // add an element
    mObserverList.AppendObject(aObserver);
...
    // iterate through the array - note we can call 
nsIObserver::Observe() directly!
    for (i=0; i< count; i++) {
      if (mObserverList[i])
        mObserverList[i]->Observe(a,b,c);
    }


nsIArray
--------
A new, simplified array implementation based on nsCOMArray<nsISupports> 
- this interface WILL BE FROZEN sometime in the 1.2 or 1.3 timeframe. 
This array is safe for embeddors to use, and may appear in frozen 
interfaces. It is scriptable, refcounted, and supports both strong and 
weak pointers. The base nsIArray interface does not allow consumers to 
modify the array. There is also nsIMutableArray, which allows the array 
to be modified.

Sample usage:
the API is very similar to nsISupportsArray, and should hopefully be 
self explanitory.

Helper routines
---------------
NS_NewArray(nsIMutableArray**) - create a new nsIArray to store 
nsISupports* objects
NS_NewArray(nsIMutableArray**, const nsCOMArray_base&) - convert an 
nsCOMArray<T> into an nsIArray
NS_NewArrayEnumerator(nsISimpleEnumerator**, nsIArray*) - create an 
enumerator for an nsIArray
NS_NewArrayEnumerator(nsISimpleEnumerator**, const nsCOMArray_base &) - 
create an enumerator based on an nsCOMArray<T> - takes ownership of all 
objects in the array at creation.

do_QueryElementAt(nsIArray*, PRUint32, nsresult*) - do_QueryElementAt 
implementation for nsIArray


Please let me know if you have any questions. I will try to follow up 
all answers to netscape.public.mozilla.xpcom

Alec

-- 
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