[swift-evolution] What about a VBA style with Statement?

[Vladimir.S]

Yes, it really looks like language construction, and I like this approach.
with (some) {
   $0... = ...
}

But should many of us copy-paste these functions in each module/project or 
this is very handful feature that we want to have in our language? What do 
you think about the proposal?

Actually I think it is even OK if such functions will be in standard lib, 
i.e. without intruducing new language construct, and we can use them 
out-of-box to have 'with' functionality.

On 13.04.2016 17:25, Sean Heber via swift-evolution wrote:
> This pair works pretty well, too, if you don’t mind free functions:
>
> func with<T>(inout this: T, @noescape using: inout T->Void) { using(&this) }
> func with<T>(this: T, @noescape using: T->Void) { using(this) }
>
> It works either with classes or mutable structs if you call it correctly and the type doesn’t matter.
>
> l8r
> Sean
>
>
>> On Apr 13, 2016, at 9:17 AM, Radosław Pietruszewski via swift-evolution <swift-evolution at swift.org> wrote:
>>
>> It can be (more-or-less) solved in library code today:
>>
>> extension NSObjectProtocol {
>>      public func with(@noescape fn: Self -> Void) -> Self {
>>          fn(self)
>>          return self
>>      }
>> }
>>
>> This way, you can do, on NSObjects:
>>
>> textLabel.with {
>> 	$0.textAlignment = .Left
>> 	$0.textColor = .darkTextColor()
>> }
>>
>> I love this pattern.
>>
>> You can also make it a function to make it work with any value of any kind (it will then take form of `with(foo) { …}`).
>>
>> Ideally, if you could write a universal extension (something like `extension Any`), you could just add this behavior, with method syntax, to everything.
>>
>> — Radek
>>
>>> On 13 Apr 2016, at 15:15, 李海珍 via swift-evolution <swift-evolution at swift.org> wrote:
>>>
>>> I recently learned some VBA and I found a very conveniently `with` statement.
>>>
>>> `with` statement can be helpful to set property for UIKit instance.
>>>
>>> for instance a UILabel instance `textLabel` ,with `with` statement we can set UILabel property like this
>>>
>>>
>>>
>>> ```swift
>>>
>>> with textLabel{
>>>
>>> .textAlignment = .Left
>>>
>>> .textColor = UIColor.darkTextColor()
>>>
>>> .font = UIFont.systemFontOfSize(15)
>>>
>>> }
>>>
>>> ```
>>>
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