Pchp.Library.Arrays.MergeRecursiveInternal C# (CSharp) Method

        private static bool MergeRecursiveInternal(PhpArray/*!*/ result, PhpArray/*!*/ array, bool deepCopy)
        {
            var visited = new HashSet<object>();    // marks arrays that are being visited

            using (var iterator = array.GetFastEnumerator())
                while (iterator.MoveNext())
                {
                    var entry = iterator.Current;
                    if (entry.Key.IsString)
                    {
                        if (result.ContainsKey(entry.Key))
                        {
                            // the result array already contains the item => merging take place
                            var xv = result[entry.Key];
                            var y = entry.Value.GetValue();

                            // source item:
                            PhpValue x = xv.GetValue();

                            // if x is not a reference then we can reuse the ax array for the result
                            // since it has been deeply copied when added to the resulting array:
                            PhpArray item_result = (deepCopy && x.IsArray && !xv.IsAlias) ? x.Array : new PhpArray();

                            if (x.IsArray && y.IsArray)
                            {
                                var ax = x.Array;
                                var ay = y.Array;

                                if (ax != item_result)
                                    ax.AddTo(item_result, deepCopy);

                                if (visited.Add(ax) == false && visited.Add(ay) == false)
                                    return false;

                                // merges ay to the item result (may lead to stack overflow, 
                                // but only with both arrays recursively referencing themselves - who cares?):
                                bool finite = MergeRecursiveInternal(item_result, ay, deepCopy);

                                visited.Remove(ax);
                                visited.Remove(ay);

                                if (!finite) return false;
                            }
                            else
                            {
                                if (x.IsArray)
                                {
                                    if (x.Array != item_result)
                                        x.Array.AddTo(item_result, deepCopy);
                                }
                                else
                                {
                                    /*if (x != null)*/
                                    item_result.Add(deepCopy ? x.DeepCopy() : x);
                                }

                                if (y.IsArray) y.Array.AddTo(item_result, deepCopy);
                                else /*if (y != null)*/ item_result.Add(deepCopy ? y.DeepCopy() : y);
                            }

                            result[entry.Key] = PhpValue.Create(item_result);
                        }
                        else
                        {
                            // PHP does no dereferencing when items are not merged:
                            result.Add(entry.Key, (deepCopy) ? entry.Value.DeepCopy() : entry.Value);
                        }
                    }
                    else
                    {
                        // PHP does no dereferencing when items are not merged:
                        result.Add((deepCopy) ? entry.Value.DeepCopy() : entry.Value);
                    }
                }

            return true;
        }