ICMP means Internet Control Message Protocol and is always coupled with the IP protocol (There’s 2 ICMP variants one for IPv4 and one for IPv6.) echo request and echo response are the two operation codes of ICMP used to implement ping. Besides the original ping program, ping might simply mean the action of checking if … Read more
NB: This answer is true for Xcode before version 9; in Version 9 Apple added the ability to automatically fix up missing protocol methods; see Guy Daher’s answer. I just created an iOS project, and headed into my UIViewController.swift file. There I declared that it implemented UITableViewDelegate: class ViewController: UIViewController, UITableViewDelegate { Now when I … Read more
The Comparable protocol extends the Equatable protocol -> implement both of them In Apple’s Reference is an example from Apple (within the Comparable protocol reference) you can see how you should do it: Don’t put the operation implementations within the class, but rather on the outside/global scope. Also you only have to implement the < … Read more
It could be that the cell is not visible at this moment. tableView:indexPathForCell returns nil in this situation. I solved this using indexPathForRowAtPoint this method works even if the cell is not visible. The code: UITableViewCell *cell = textField.superview.superview; NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:cell.center];
It seems there are two use-cases of why you may want to do what you are doing. In the first use-case, Swift will allow you to do what you want, but not very cleanly in the second use-case. I’m guessing you fall into the second category, but I’ll go through both. Extending the functionality of … Read more
Nice question. Here is my humble point of view: Is there a point to declaring a static function on a protocol? Pretty much the same as having instance methods declared in a protocol. The client using the protocol has to call the function on a type conforming to the protocol anyway right? Yes, exactly like … Read more
Have you considered HDLC or SDLC? There’s also LAP/D (Link Access Protocol, D-Channel). Uyless Black’s “Data Link Protocols” is always nearby on my bookshelf – you might find some useful material in there too (even peruse the TOC & research the different protocols)
I wouldn’t say that something uses a wire-level protocol or doesn’t – I’d talk about which wire-level protocol it uses. Basically, if something’s communicating with a remote machine (even conceptually) then there’s some data going across the network connection (the wire). The description of that data is the “wire-level protocol”. Even within that, you would … Read more
You Just Can’t Beat the Binary Binary protocols will always be more space efficient than text protocols. Even as internet speeds drastically increase, so does the amount and complexity of information we wish to convey. The text protocols you reference are outstanding in terms of standardization, flexibility and ease of use. However, there will always … Read more
You could use a protocol composition: extension Moveable where Self: protocol<Animal, Aged> { // … } Or just add the conformances one after the other: extension Moveable where Self: Animal, Self: Aged { // … }