[PowerWyrm]

I thought I'd post this here. It's a little function that I added while porting the struct loc refactoring to PWMAngband to make some code clearer. Here it is:

bool loc_iterator(struct loc *iter, struct loc *grid1, struct loc *grid2, bool strict)
{
    iter->x++;
    if (iter->x == (strict? grid2->x: grid2->x + 1))
    {
        iter->x = grid1->x;
        iter->y++;
        if (iter->y == (strict? grid2->y: grid2->y + 1)) return false;
    }
    return true;
}

This allows to change the following code:

for (y = y1; y < y2; y++) {
for (x = x1; x < x2; x++) {
foo(y, x);
}
}

into:

loc_copy(&iter, &grid1);
do {
foo(&iter);
} while (loc_iterator(&iter, &grid1, &grid2, true)); (or "false" to do "<=" instead of "<")

I've removed most of the ugly x/y loops that way.