If I have a range like this, how do you find its last item using
Phobos?
A simple way is to use seq.array.back, but this wastes memory.
Another simple way is to use a foreach loop keeping the last
seen. But do you know if there is a function to do in Phobos? And
if such function is not present (walkBack? backWalk?) is it a
good idea to add it to Phobos?
void main() {
import std.stdio, std.algorithm, std.range;
int m = 75;
auto seq = recurrence!q{ a[n - 1] + a[n - 2] }(1, 1)
.until!(x => x > m)(OpenRight.no);
seq.array.back.writeln; // 89
//seq.back.writeln;
auto last = -1;
foreach (immutable x; seq)
last = x;
last.writeln;
}
Bye,
bearophile
