UPDATE 2: I've added a new post about the changes in Beta 3 (I like them)

UPDATE - Apple have indicated that the array behaviour in Swift is going to change - see this post

Update 3: Please note that this article remains for the historical record and to ensure that links in other articles aren't broken but that the behaviour of Swift arrays was radically changed in Beta 3 and it resolves most if not all of the issues that I had with Swift arrays making the following essentially redundant. Update 2 above links to my follow up article reviewing the changes. You can also read several of my more recent articles about Swift. [This presentation about optimising Swift is particularly recommended and this article about mutating Swift arrays from multiple threads is on topic with this post. - Update 4]

I really like Apple's new Swift language. It brings in some of the best features of many functional languages including ML, to Haskell such as type inference, strong types, generic types and combines them with with an object system that can interoperate with the existing frameworks while still being fast and efficient. It encourages immutable values over variables and will eliminate whole classes of errors related to null pointers and improper handling of them.

The main thing that I don't like about it is the handling of "immutable" arrays. For performance reasons when an array is declared with "let" it means only that the array length is immutable and other arrays cannot be assigned to the same variable. You can however change any of the values in the array. I think that almost whatever the performance gains this is not worth the confusing behaviour that results. [Edit: Follow up post explaining the current behaviour is now available.]

In the post I will mix speculation and a little investigation of the behaviour to understand what the current behaviour is and the rationale for it. I also intend to propose a way out of the situation by which the behaviour could be changed with minimum disruption. Apple has indicated that source compatibility is not guaranteed to be maintained and I think automatic conversion would be possible to migrate code.

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When Interface Builder doesn't do what you want Hack the Storyboard XML

I like Autolayout and the concepts behind it. I also like using Interface Builder to see the relationships I'm creating but there isn't quite the right degree of flexibility and control (at least as of Xcode 5.1.1).  This post shows how you can convince Interface builder to do your will when it doesn't want to let you create quite the layout that you want you can directly edit the Storyboard XML to enable the effect that you want (and subsequently view it and tweak it in Interface Builder).

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iOS 7.1 Strongly Recommended

Based on the (lack of) crash reports that I have received so far for Fast Lists iOS 7.1 is much more stable and most of the issues I had open were probably actually iOS bugs rather than Fast Lists bugs. So far I have received only two crashreports pertaining to iOS 7.1 and both are apparently the same (new) issue although I have not investigated deeply yet.

All Users should update to Fast Lists 2.04 ASAP (or 1.78 if you can't install iOS 7)

To Apple employee that crashed Fast Lists 1.72 on 2nd April on an iPad

That is probably my bug please update to the latest Fast Lists, 1.72 had serious crashing issues although I obviously haven't tried it on the iOS version you are using which may resolve some of them.

UPDATE This crash seems to have stopped occurring since iOS 7.1 was release. At this time (4th April) I haven't seen any occurrences on iOS 7.1 when I was seeing it more about weekly on iOS 7.0x. Several other crash types have also not been observed on iOS 7.1 although two instances of a different crash have been seen.

Most software crashes sometimes and unfortunately this includes Fast Lists. At the moment I have records of 12 crashes in the latest version (2.04) that was released about a month ago (18th Feb). On many occasions crashes are clearly caused within the software I have developed whether due to my mistake or the libraries (both Apple and 3rd party) that I use having bugs and not and not behaving as documented.  This post is about several crash reports that appear to be occurring deep within Apple's code (although quite possibly due to my own incorrect software), it includes the crash reports very slightly redacted and what I have currently deduced about the cause.

I think the general interest in this post for non-developers will be pretty close to zero.

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It is some initial thoughts and experiences with using Docker for about a week. Specifically I was getting JIRA up and running in Docker on Rackspace for my own use (and it directly receives crash reports from some of my iOS apps). I also used it on my home server to set up a build environment for a JIRA plugin.

Update - Rackspace Cloud Servers Advice

Rackspace Cloud Servers are currently configured with no swapfile. I strongly recommend following the instructions to create a swapfile otherwise once you hit the limit of your server memory it will kill a process (probably your biggest which could well be Java).

General Docker Thoughts

Docker is nice, new containers spin up quickly, the documentation is OK. It is still pre-1.0 so moving fast and much of the online articles about it are out of date already. This isn’t really the first place you should look for information so I’m generally not going to explain syntax or concepts except to give my understanding of the difference between images and containers.

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