Preserving order with LINQ

I use LINQ to Objects instructions on an ordered array.
Which operations shouldn't I do to be sure the order of the array is not changed?

I examined the methods of System.Linq.Enumerable, discarding any that returned non-IEnumerable results. I checked the remarks of each to determine how the order of the result would differ from order of the source.

Preserves Order Absolutely. You can map a source element by index to a result element

• AsEnumerable

• Cast

• Concat

• Select

• ToArray

• ToList

Preserves Order. Elements are filtered or added, but not re-ordered.

• Distinct

• Except

• Intersect

• OfType

• Prepend (new in .net 4.7.1)

• Skip

• SkipWhile

• Take

• TakeWhile

• Where

• Zip (new in .net 4)

Destroys Order - we don't know what order to expect results in.

• ToDictionary

• ToLookup

Redefines Order Explicitly - use these to change the order of the result

• OrderBy

• OrderByDescending

• Reverse

• ThenBy

• ThenByDescending

Redefines Order according to some rules.

• GroupBy - The IGrouping objects are yielded in an order based on the order of the elements in source that produced the first key of each IGrouping. Elements in a grouping are yielded in the order they appear in source.

• GroupJoin - GroupJoin preserves the order of the elements of outer, and for each element of outer, the order of the matching elements from inner.

• Join - preserves the order of the elements of outer, and for each of these elements, the order of the matching elements of inner.

• SelectMany - for each element of source, selector is invoked and a sequence of values is returned.

• Union - When the object returned by this method is enumerated, Union enumerates first and second in that order and yields each element that has not already been yielded.

Edit: I've moved Distinct to Preserving order based on this implementation.

private static IEnumerable DistinctIterator
      (IEnumerable source, IEqualityComparer comparer)
    {
        Set set = new Set(comparer);
        foreach (TSource element in source)
            if (set.Add(element)) yield return element;
    }

Stack Overflow Q#204505, score: 770