<div dir="ltr">None taken. However, most of the delegate concept of UIKit relies heavily on this "nonsensical" requirement. It is impossible for someone to implement a control in swift which is "in the spirit" of UIKit, meaning the control has a delegate, with several methods that share the same name with different parameters, some are required and some are optional. I think it is not fair to tell users that they cannot implement something that is such a common and repeating pattern in the core. </div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Mar 31, 2016 at 2:23 PM, Dave Abrahams via swift-evolution <span dir="ltr"><<a href="mailto:swift-evolution@swift.org" target="_blank">swift-evolution@swift.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class=""><br>
on Wed Mar 30 2016, Yuval Tal <<a href="mailto:swift-evolution@swift.org">swift-evolution@swift.org</a>> wrote:<br>
<br>
> Hi,<br>
><br>
> I find that optional protocol methods to be very useful. However,<br>
> there is a caveat -- it needs to be mapped to @objc. This puts a set<br>
> of limitations, such as: structures cannot be used as parameters as it<br>
> does not map to objective-c. What do you think about removing the<br>
> requirement of using @objc and allow to create optional methods<br>
> without these limitations?<br>
<br>
</span>Caveat: this is going to be strongly-worded; sorry in advance. I think<br>
(no offense intended) it's a terrible idea. The whole notion of an<br>
“optional requirement” is nonsensical to begin with, and the use of<br>
optional protocol requirements encourages a style of programming that<br>
lifts the responsibility of the protocol designer for careful design at<br>
the expense of clients of the protocol. There are better ways to do<br>
things; let's not propagate this anti-pattern any further than it's<br>
already gone.<br>
<span class="HOEnZb"><font color="#888888"><br>
--<br>
Dave<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
_______________________________________________<br>
swift-evolution mailing list<br>
<a href="mailto:swift-evolution@swift.org">swift-evolution@swift.org</a><br>
<a href="https://lists.swift.org/mailman/listinfo/swift-evolution" rel="noreferrer" target="_blank">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br>
</div></div></blockquote></div><br></div>