On Wed, Jul 01, 2020 at 07:02:39AM +0100, Christoph Hellwig wrote: > Hi Matthew, > > I'm just reviewing a patch adding an xarray user, and I'm wondering > if we could just replace xa_for_each with a loop on > xa_find_after with a magic index to start from the beginning? That > would always seem like more readable code than the magic looping macro.
The problem is that there is no index we can use for that purpose. xa_find_after(0) should return the entry at 1 (or higher). xa_find_after(ULONG_MAX) should return NULL. The xas_ version doesn't have this problem because we can distinguish between "first time" and "subsequent time" by values in the xa_state. > And while we're at it: is there an idiomatic way to get the entry with > the highest index? That's something I need to add. I think I did it once but then the user went away.
