On 09/17/2012 03:51 PM, Andrej Mitrovic wrote:
On 9/18/12, Ali Çehreli<[email protected]> wrote:
I think you actually want .shortest, no?
No I want to continue iterating as long as one of the ranges is still
not empty. I'm not doing just comparisons, once there's only one range
that's not empty I have to do some special checks on its elements. In
simple terms:
void main()
{
enum sentinel = -1;
// imagine 3rd element missing and lockstep replaces it with -1
int[] arr1 = [2, 4, -1];
int[] arr2 = [2, 4, 3];
bool state;
foreach (aa, bb; lockstep(arr1, arr2))
{
if (aa == sentinel)
{
if (aa % 2 == 0)
{
state = true;
break;
}
}
else
if (bb == sentinel)
{
if (bb % 2 == 0)
{
state = true;
break;
}
}
else
{
if (aa == bb)
{
state = true;
break;
}
}
}
}
That's not the algorithm I'm using and I'm not dealing with integers
but that's just an example. If either range is empty I want to
continue doing some special work on the range that isn't empty,
otherwise I have to do work on both.
Then .longest with zip seems to be the way to go. zip() produces the
.init value for the short range. Luckily, you are not dealing with
int.init so perhaps your type's sentinel is distinguishable:
foreach (aa, bb; zip(StoppingPolicy.longest, a, b))
{
if (aa == aa.init) {
}
// etc.
writefln("%s and %s", aa, bb);
}
Ali
