On 06/02/2016 02:51 PM, Steven Schveighoffer wrote:
For example, generate.popFrontN does nothing. generate.drop does nothing. And of course, calling front multiple times does not yield the same answer, unless you provide a lambda that does the same thing every time (a useless case).
That's just broken.
The counter-argument seems to be that if you cache the front element, then then making a copy of the range via take can repeat the cached element[4]. I find this argument severely lacking -- non-forward ranges are not meant to be copied and expected to operate properly, it's why we require calling save.
Completely agree with you here. You can only use one of the copies. When you call popFront on one of them, that invalidates the other one. To get two valid copies, use .save.
generate should not try to go beyond the contract here when it means broken behavior elsewhere.
