On 11/10/15 9:28 AM, Shachar Shemesh wrote:
Please consider the following program:
The problem is that you defined a forward range without implementing all the primitives :) That is, you can easily make a copy of the range so it iterates from the current spot (the quintessential feature of forward ranges). You actually have to do *extra work* to make it a true input-but-not-forward-range.
I've never made it a secret that I dislike the 'save' requirement. In my experience, the only time you ever implement 'save' is to do the same thing as copying the range via =. To the point where people simply don't use the .save member, and their code always works, so what is the point? It may as well have been an enum isCopyable.
-Steve
