Should this work?

[John Colvin]

On Friday, 10 January 2014 at 15:05:18 UTC, monarch_dodra wrote:
> On Friday, 10 January 2014 at 14:31:31 UTC, John Colvin wrote:
>> or if you want something short and simple, define a free 
>> function:
>> auto popFrontRet(R)(ref R range)
>>    if(isInputRange!R)
>> {
>>    range.popFront();
>>    assert(!range.empty);
>>    return range.front;
>> }
>
> *Unless* I'm mistaken, he was asking for something that returns 
> the *popped* element?
>
> Re-reading the question, it does kind of sound a bit ambiguous 
> now.

Woops, of course:

auto popFrontRet(R)(ref R range)
     if(isInputRange!R)
{
     auto tmp = range.front;
     range.popFront();
}


That also invalidates my second point to do with emptiness.