private static IList <ITypeParameter> GetOuterTypeParameters(ITypeMemberDeclaration typeMemberDeclaration)
        {
            var typeDeclaration = typeMemberDeclaration.GetContainingTypeDeclaration();
            var parameters      = typeDeclaration?.DeclaredElement?.GetAllTypeParameters();

            return(parameters?.ResultingList() ??
                   EmptyList <ITypeParameter> .Instance);
        }