[swift-evolution] InternalString class for easy String manipulation

Xiaodi Wu xiaodi.wu at gmail.com
Mon Aug 22 20:44:38 CDT 2016


On Sun, Aug 21, 2016 at 3:04 PM, Richard Ward via swift-evolution <
swift-evolution at swift.org> wrote:

> First, this is my first post to a list like this and I could not find the
> instructions to properly respond to a post in the digest.  Does one have to
> subscribe to the verbose (non digest post) in order to respond to a thread
> correctly?  Or is there a link to some instructions?   Thanks.
>

Welcome! Sadly, I don't know of any way to reply to the right thread from
the digest.


> I come from a scientific/engineering background where I create a lot of
> utility applications which do not have to be as robust in certain ways as
> commercial applications which are used by a mass number of people.  To be
> clear, the applications need to work and produce correct results and need
> to be robust in this way.  Python is used by a large portion of the
> scientific community to create applications such as I mentioned and in
> large part due to what Michael stated in his original email.  I dislike
> having to scan/read code which has long multiply nested method trains such
> as
>
> str.characters.count      where to me, it is easier to scan/read code such
> as        str.len or len(str)
>

I come from a scientific background too and know and love Python (well,
*knew*, back in the good ol' 2.* days). Unicode in Python 2 was, if I
recall correctly, not exactly a bright spot.

This argument is not persuasive to me. The same issue about long spellings
(as compared to other languages) applies pervasively in Swift, but as far
as I can tell, in each case brevity is deliberately taking a backseat to
correctness. I expect you're bound to encounter, if you ever try (for
example) to read a binary format for scientific/engineering uses, spellings
such as `UnsafeMutableBufferPointer` and others new to Swift 3 such as
`UnsafeRawPointer(ptr).bindMemory(to: T.self)`, `MemoryLayout<T>.size(of:
value)`, etc. Each of these is significantly longer than the spelling of
similar facilities in, say, C or Python. But it reflects Swift naming
guidelines, which were one of the main focuses of Swift 3 evolution. IMO,
what you're advocating for, if applied throughout Swift APIs, would be a
very broad shift in a diametrically opposite direction on a settled issue.

One Swift renaming that sticks out to me as taking the "Swift way" to its
epitome, having skimmed some of the API notes, is this one:

```
  - Name: NSTimeIntervalSince1970
    SwiftName: timeIntervalBetween1970AndReferenceDate
```

I understand the need for unicode in general purpose / internationalized
> applications.   However, it is overkill for most of what I need to do.
> Also, I agree with Michael that learning the unicode way of Swift is a
> barrier to people new to coding.
>
> I am wondering why one can’t make a method extension for String called
> .len or .length (and for that case make a commonly used subscript extension
> as well) which conform to a protocol which is constructed as only taking
> say ascii or simplified string?s  This could be put into a “semi-standard”
> library and people who needed/wanted a simplified interface could access
> and use it?  Couldn’t the existing dull underlying string structure be used
> for this?
>

The beauty of Swift is that it is easy to do this for your own code, and
easy to do it correctly. My take would be that your own code would be where
such an approach would be most "Swifty."


> I also don’t like to have to perform type conversions between floating
> point numbers but that is for another thread.
>
> ——
>
> On Aug 15, 2016, at 1:00 PM,  Michael Savich <savichmichael at icloud.com>
> wrote:
>
>
> Back in Swift 1.0, subscripting a String was easy, you could just use
> subscripting in a very Python like way. But now, things are a bit more
> complicated. I recognize why we need syntax like
> str.startIndex.advancedBy(x) but it has its downsides. Namely, it makes
> things hard on beginners. If one of Swift's goals is to make it a great
> first language, this syntax fights that. Imagine having to explain Unicode
> and character size to an 8 year old. This is doubly problematic because
> String manipulation is one of the first things new coders might want to do.
>
>
> <snip>
>
> On Aug 15, 2016, at 8:24 PM,Xiaodi Wu <xiaodi.wu at gmail.com> wrote:
>
> <snip>
>
> But, we also want Swift to support Unicode by default, and we want that support
> to do things The Right Way(TM) by default. In other words, a user
> should not have to reach for a special type in order to handle arbitrary strings
> correctly, and I should be able to reassign `a = "你好"` and have things
> work as expected. So, we also can't have the "easy" string type be the
> default...
>
>
> _______________________________________________
> swift-evolution mailing list
> swift-evolution at swift.org
> https://lists.swift.org/mailman/listinfo/swift-evolution
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-evolution/attachments/20160822/9de35dd2/attachment.html>


More information about the swift-evolution mailing list