Sent from my iPhone

> On 12 Apr 2017, at 01:18, Jakub Suder via swift-evolution 
> <[email protected]> wrote:
> 
> I'm honestly having trouble believing that this is being seriously 
> proposed... I always saw type inference as one of the most important 
> advantages of Swift over some older languages, the Swift ebook mentions many 
> times how smart Swift is that it can infer types for you so that you don't 
> have to type too much boilerplate.

I think Swift and its compiler have. A lot of other strong points beyond type 
inference and emphasis on static typing too, but type inference has a very very 
real cost and sooner or later the language and its community will have to deal 
with compile times that are a lot slower (some people were reporting about 2+ 
times slower) than a similar project in Objective-C... that is a very real 
productivity cost.

> And here we're talking about removing this feature that was advertised from 
> the beginning as Swift's strong point, in order to make the compilation 
> faster? The compiler speeds will be improved, the syntax will stay with us.
> 
> Yes, specifying the type is often clearer, I do it myself, e.g. "var enabled: 
> Bool = true". But that's my choice, not something I should be forced to do. 
> It's something to put in style guides, not to enforce with the compiler.
> 
> 
>> On 8 April 2017 at 07:40, Pranshu Goyal via swift-evolution 
>> <[email protected]> wrote:
>> I agree with the sentiment of the proposal, it does add value to overall 
>> efficiency of swift and make things simpler for the swift team, but as 
>> Matthew said a blanket ban will add noise to the code. Also this particular 
>> feature is one of those niceties about swift which makes it very welcoming 
>> to new adopters.
>> 
>> If some middle ground can be proposed to this problem then I think we will 
>> be making a lot of people happy.
>> 
>>> On 7 April 2017 at 18:31, Matthew Johnson via swift-evolution 
>>> <[email protected]> wrote:
>>> 
>>> > On Apr 7, 2017, at 2:21 AM, Daniel Duan via swift-evolution 
>>> > <[email protected]> wrote:
>>> >
>>> > Hi all,
>>> >
>>> > In a discussion about inferring parameter types from default value, Slava 
>>> > brought up some performance problems caused by type inference for stored 
>>> > properties in side types:
>>> >
>>> > https://lists.swift.org/pipermail/swift-evolution/Week-of-Mon-20170313/033882.html
>>> >
>>> > Towards the end, the post mentioned that some Swift team members 
>>> > contemplated requiring types for stored properties in type declarations. 
>>> > I think this idea deserves some more attention. Hence this last minute 
>>> > idea-floating.
>>> >
>>> > In addition to solving a performance headache in implementation, there're 
>>> > always the general benefit of making type declartion more explicit and 
>>> > readable (clarity for reader should out-weigh pleasure of the author). 
>>> > Making the
>>> > language slightly more consistent (we are not inferring types for default 
>>> > parameter values in function anyways).
>>> >
>>> > The cons for doing this are obvious too: the inference makes the language 
>>> > feels more friendly and is, undoubtedly, a beloved feature for many. This 
>>> > would be a source breaking change.
>>> >
>>> > Just thought I'd float the idea to gather some quick reaction. What do 
>>> > y'all think?
>>> 
>>> I’m willing to keep an open mind on this topic but I don’t think wholesale 
>>> banning of inference is the right thing to do.  Here is an example of a 
>>> case where I do not want to give up inference.  When a property is 
>>> initialized inline by calling an initializer of a non-generic type (very 
>>> common) any annotation is strictly redundant.
>>> 
>>> struct {
>>>     let foo = Foo()
>>> }
>>> 
>>> Requiring a type annotation here feels very unnecessary and boilerplate-y.  
>>> I adds no additional clarity to a reader of the code, only noise.  Noise 
>>> reduces clarity.  Small amounts of unnecessary or redundant information 
>>> such as in an individual stored property declaration are not that big a 
>>> deal.  But on balance they add up quickly and have an undesirable impact on 
>>> the overall clarity of code.
>>> 
>>> >
>>> > Daniel Duan
>>> > _______________________________________________
>>> > swift-evolution mailing list
>>> > [email protected]
>>> > https://lists.swift.org/mailman/listinfo/swift-evolution
>>> 
>>> _______________________________________________
>>> swift-evolution mailing list
>>> [email protected]
>>> https://lists.swift.org/mailman/listinfo/swift-evolution
>> 
>> 
>> 
>> -- 
>> Pranshu Goyal
>> iOS Developer
>> tlkn
>> 
>> _______________________________________________
>> swift-evolution mailing list
>> [email protected]
>> https://lists.swift.org/mailman/listinfo/swift-evolution
>> 
> 
> _______________________________________________
> swift-evolution mailing list
> [email protected]
> https://lists.swift.org/mailman/listinfo/swift-evolution
_______________________________________________
swift-evolution mailing list
[email protected]
https://lists.swift.org/mailman/listinfo/swift-evolution

Reply via email to