Please, almost anything but going back to the horrible Objective-C pattern of 
private headers (that end up included on in the implementation files) :/.

Seriously, that was always my issue with that blog post, assuming that the 
Objective-C way of dealing with this issue was something worth moving forward 
and not a path to massively improve upon or to avoid.

Sent from my iPhone

> On 20 Feb 2017, at 08:30, Jonathan Hull via swift-evolution 
> <[email protected]> wrote:
> 
> 
>> On Feb 19, 2017, at 7:29 PM, David Waite via swift-evolution 
>> <[email protected]> wrote:
>> 
>> A third point (which is a bit more complex/convoluted) is that fileprivate 
>> remained an essential language feature because it allows implementation in 
>> extensions, and allows a simple “friend”-like feature where types that need 
>> access to implementation details due to higher coupling could be bundled 
>> into the same file. Outside of a desire of a scoped ‘private’ simply to 
>> match the behavior of certain other languages, private is used to hide 
>> implementation details from other parts of a file, while file private 
>> exposes them within the file. 
>> 
>> There is a potential that file-private can lead to an explosion of 
>> complexity due to a large amount of “friendly types” being bundled into the 
>> same file. In that sense, ‘private’ was wrong because it was adding 
>> complexity at the file level, when really a new access level would possibly 
>> have been more productive to define at the at the small-group-of-files level 
>> - either via a friend access level or submodules. We still have the 
>> potential of unmanageable files due to friend types, but any additional 
>> access levels to aid with this problem would have to be weighed against a 
>> now significantly more complex access model including file and scoped 
>> private. In that sense, the inclusion of scoped private may indeed be 
>> harmful in that it increases the challenge of much more useful access levels 
>> being added to the language.
> 
> This is the core of what I have been saying.  If we don’t address this need 
> of “friendly types” in a swift-y way, we will have to keep coming back to the 
> drawing board (either for “friend” or “protected” or “submodules”).  I really 
> like swift 2 private, but it did cause long files because all of the 
> extensions and friends had to be stuck in the same file. What we are really 
> missing is something that has the connotation similar to private, but allows 
> access where needed.
> 
> I agree with most of what was said in this blog post from the swift devs:
> https://developer.apple.com/swift/blog/?id=11
> 
> The main exception is that I disagree that ‘internal’ maps to the ObjC case 
> where a second header was used (it doesn’t, and that is what is causing all 
> of this trouble).  Because internal is the default, it feels much too easy to 
> accidentally use parts of a type which should only be used by 
> extensions/subclasses/friend types. Remember, in an app (as opposed to a 
> framework), internal is basically equivalent to public.  With the second 
> header, users of the contents of that header had to explicitly include it, 
> which meant there was no chance of accidental use.
> 
> What we need is something which maps to that second header case while still 
> keeping everything conceptually simple and swift-y.
> 
> Thanks,
> Jon
> 
> 
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