Andrei, as the topic just came up a comment on the range interface.
Just for plain forward iterators iterators having
bool empty()
E front()
void popFront()
makes the interface non reentrant.
For that purpose having a single function is better.
I use
bool popFront(ref T t)
// returns true if there is a next element, and in that case returns
it in t
this can be used by several consumers concurrently without problems
and creating filters, combiners,... is simple.
Another advantage is that a single object can implement several
iterators.
A disadvantage is that even if there is a single iterator D makes type
inference cumbersome, i.e. you cannot simply use auto, as in a loop
you have to declare the variable before using it as the loop is
T a;
while (it.popFront(a)){
//...
}
