Higher Order Range Pattern

[Dennis Ritchie via Digitalmars-d-learn]

On Monday, 22 June 2015 at 15:25:12 UTC, Steven Schveighoffer 
wrote:
> On 6/22/15 11:04 AM, Dennis Ritchie wrote:
>> Hi,
>> I recently came across the following code:
>> http://wiki.dlang.org/Higher_Order_Range_Pattern
>>
>>
>> I can't understand why the properties and methods of the 
>> structure are
>> called in the correct order.
>> Why are the property `back()` and the method `popBack()` are 
>> not called
>> even once?
>
> Because std.algorithm.equal does not use back or popBack.
>
>> In general, please explain how it all works.
>
> I have a feeling you are not understanding something. This code 
> is pretty straightforward, I don't know what else to explain 
> about it.
>
> -Steve

Thanks. I understand everything, just std.algorithm.equal 
introduced me to the great confusion :)
Now everything fell into place.