std.range.chain bug?

[monarch_dodra]

On Monday, 25 November 2013 at 23:44:26 UTC, Jonathan M Davis 
wrote:
> On Monday, November 25, 2013 22:08:37 monarch_dodra wrote:
>> On Monday, 25 November 2013 at 21:04:43 UTC, Jesse Phillips 
>> wrote:
>> > On Monday, 25 November 2013 at 19:38:44 UTC, Jack Applegame
>> > 
>> > wrote:
>> >> This isn't compiles. Bug?
>> >> 
>> >> import std.range;
>> >> class Foo {}
>> >> void main() {
>> >> 
>> >> immutable(Foo)[] a;
>> >> immutable(Foo)[] b;
>> >> auto c = chain(a, b).length;
>> >> 
>> >> }
>> >> 
>> >> http://dpaste.dzfl.pl/71272a10
>> > 
>> > Seems like a bug to me. If Foo where a string I'd expect it 
>> > to
>> > fail, but what you have looks reasonable.
>> 
>> Really? Why? As a matter of fact, it *works* with string...
>
> What works with string? chain(a, b).length had better not work 
> if either a or
> b is a string, because hasLength is false for narrow strings.
>
> - Jonathan M Davis

Right, but he said "Foo":

import std.range;
alias Foo = string;
void main() {
	immutable(Foo)[] a;
	immutable(Foo)[] b;
	auto c = chain(a, b).length;
}