Boo.Lang.Compiler.TypeSystem.TypeSystemServices.GetGenericEnumerableItemType C# (CSharp) Method

        public IType GetGenericEnumerableItemType(IType iteratorType)
        {
            // Arrays implicitly implement IEnumerable[of element type]
            if (iteratorType is ArrayType) return iteratorType.ElementType;

            // If type is not an array, try to find IEnumerable[of some type] in its interfaces
            IType itemType = null;
            foreach (IType type in GenericsServices.FindConstructedTypes(iteratorType, IEnumerableGenericType))
            {
                IType candidateItemType = type.ConstructedInfo.GenericArguments[0];

                if (itemType != null)
                    itemType = GetMostGenericType(itemType, candidateItemType);
                else
                    itemType = candidateItemType;
            }

            return itemType;
        }