[swift-users] Range.count can abort

I’m writing some code that deals with ranges of “sequence numbers”, which are consecutively-assigned positive 64-bit integers, thus Range in Swift. I’m having trouble handling half-open ranges with no maximum, which are very commonly used for representing all items created since a certain time.

Re: [swift-users] Range.count can abort

> On Apr 16, 2016, at 12:53 PM, Dmitri Gribenko wrote: > > It needs to be a signed integer. And a signed integer needs a distance type > itself. Yeah, there’s an infinite regress implied there, since a distance type has to be one bit larger than its source type. The

Re: [swift-users] Range.count can abort

On Sat, Apr 16, 2016 at 8:29 AM, wrote: > Is there any reason that Distance has to be a simple Int? Since it’s defined > per-type, UInt64 could use a custom struct without impacting the performance > of other types: It needs to be a signed integer. And a signed integer

Re: [swift-users] Range.count can abort

Is there any reason that Distance has to be a simple Int? Since it’s defined per-type, UInt64 could use a custom struct without impacting the performance of other types: struct UInt64Distance : Comparable { //I'm not sure what else it needs to conform to var distance: UInt64 var

Re: [swift-users] Range.count can abort

On Fri, Apr 15, 2016 at 4:41 PM, Jens Alfke wrote: > > > --Jens [via iPhone] > >> On Apr 15, 2016, at 4:26 PM, Dmitri Gribenko wrote: >> >> The distance is signed so that we can represent negative distances. >> r.distance(from:to:) should be able to

Re: [swift-users] Range.count can abort

--Jens [via iPhone] > On Apr 15, 2016, at 4:26 PM, Dmitri Gribenko wrote: > > The distance is signed so that we can represent negative distances. > r.distance(from:to:) should be able to measure distances backwards. Yeah, makes sense in general, just not for this