Re: [boost] [range] RFC: span(iterator, size)

30 Oct 2013


      2013/10/30 Evgeny Panasyuk 
...
30.10.2013 11:29, TONGARI J:
...
1. So, span(first, n) and span(next(first), n) will result in "equal"
...
iterators?
if you mean begin-or-end(span(first, n)) == begin-or-end(span(next(first),
n)), then yes, but it's pathic.
Yes, that what I mean. This limitation should be placed as warning.
Especially you mentioned that you plan to preserve same range category as
...
...
...
original iterator has - what about BidirectionalIterators?
That's my mistake, they should be ForwardIterators.
1. What about RandomAccessIterators?
For RandomAccessIterators, 'span' will return the iterator as is, no
wrapping.
...
2. Imagine if we have std::list x with 10 elements. Will dereference of
end(span(begin(x), 5)) be undefined?
It's defined to be non-dereferenceable.