> On Mar 15, 2017, at 8:21 PM, Nicholas Maccharoli <nmacchar...@gmail.com>
> wrote:
>
> Jaden,
>
> Yes that error message is not so great.
> As for the use of guard `if someCondition { fatalError(...)}` seems to be a
> common way of phrasing fatal errors
> in the standard library but guard works just as well.
I’d guess that’s because most of the standard library predates the existence of
`guard`, but I’m not sure! Either spelling is probably fine (and more the topic
of a pull request than a SE review 🙂).
>
> I updated the proposal to have the following definition:
>
> extension Strideable where Stride: Integer {
> func clamped(to range: Range<Self>) -> Self {
> guard !range.isEmpty { fatalError("Can not clamp to an empty range.")
> }
> return clamped(to: range.lowerBound...(range.upperBound - 1))
> }
> }
>
> - Nick
>
> On Thu, Mar 16, 2017 at 11:57 AM, Jaden Geller <jaden.gel...@gmail.com
> <mailto:jaden.gel...@gmail.com>> wrote:
>
>> On Mar 15, 2017, at 7:33 PM, Nicholas Maccharoli <nmacchar...@gmail.com
>> <mailto:nmacchar...@gmail.com>> wrote:
>>
>> Right, there were a few things missing!
>> Thanks so much for pointing them out everyone.
>>
>> Dave - Great idea! I have updated the motivation section section as you
>> suggested!
>>
>> Neil - Yes I also think the wording could be a bit better but since the word
>> `clamped` is already being used
>> I thought I would keep it consistent.
>>
>> Sean - Looks as if its a term of art to me as well.
>>
>> Nate,
>>
>> Good catch! Yes I also thing clamping on an empty range should be a fatal
>> error as well.
>> An empty range is impossible to create with `ClosedRange` so I left the
>> implementation
>> of that alone, but it is possible with `Range` so I updated the extension on
>> `Strideable` like so:
>>
>> extension Strideable where Stride: Integer {
>> func clamped(to range: Range<Self>) -> Self {
>> if range.isEmpty { fatalError("Can't form Range with upperBound <
>> lowerBound") }
>> return clamped(to: range.lowerBound...(range.upperBound - 1))
>> }
>> }
>>
>>
>>
>> Jaden,
>>
>> Yeah I think a simple `if` check would work as well.
>
> I would suggest using guard. It is more idiomatic Swift for something that
> “fails out”.
>
> Also, I think this is a bad error message. The `Range` was already created!
> There was no problem forming it. It was passed as the argument, no problem at
> all. The problem is trying to *clamp* to an empty range, not forming an empty
> range. I would rephrase it to say something like "Cannot clamp to an empty
> range”. No reason to redefine what an empty range is by mentioning
> `upperBound < lowerBound`.
>
> Cheers,
> Jaden Geller
>
Cheers,
Jaden Geller_______________________________________________
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