Inside Swift

http://www.eswick.com/2014/06/inside-swift/

by pohl • 12 years ago

51 24 12 years ago

saurik3• 12 years ago

I also covered some of this (in fact, last I saw this article, much more than is here, but I can't see the article right now because it is just saying there is a database error) in my talk at AltConf (during WWDC), where I used Hopper and Cycript (my Objective-C/JavaScript hybrid debug REPL) to demonstrate the layout of a Swift object (as well as taking some questions afterwards from the audience).

https://www.youtube.com/watch?v=Ii-02vhsdVk

_Zach• 12 years ago

All the 'I also _____' and 'me too me too!!!' comments are so distasteful.

tendom• 12 years ago

I'm new to HN, but are you new to the internet? Saurik knows a few things about iOS, google him.

coldtea• 12 years ago

"Me too"-ism? Are tutorials and articles on a new language only supposed to be written by one single person?

Or should any other who has written related material not inform HN, because someone other's articles were posted first?

iheart2code• 12 years ago

The site appears to be down. Here is the cached version: http://webcache.googleusercontent.com/search?q=cache:rOWlIup...

tempodox2• 12 years ago

Thanks. Demand must be tremendous because that site doesn't respond either.

D4AHNGM• 12 years ago

Thanks for this link. The site still seems to be down, 9 hours later.

agentcoops• 12 years ago

"Swift is Apple’s new programming language, said by many to ‘replace’ Objective-C. This is not the case. I’ve spent some time reverse engineering Swift binaries and the runtime, and I’ve found out quite a bit about it."

Correct me if I'm wrong (and my point certainly isn't meant to detract from the interest of looking more in-depth at Swift internals), but this article doesn't appear to support this claim at all. It seems equivalent to saying Scala isn't meant to replace Java, or C assembly, because at the end of compilation it's all just Java. Abstraction is real. Also, Apple is providing a "migration guide" for porting Objective-C apps over to Swift. Nothing is conclusive, obviously, but certainly the article does not show that Apple doesn't intend for Swift to ultimately replace Objective-C as the primary language of Mac development.

gilgoomesh• 12 years ago

Yeah, the article's technical analysis is good but I'm not sure what this line was supposed to say: what it actually says is wrong. Swift is definitely intended to replace Objective-C.

Perhaps that line in article meant that it's not binary identical to Objective-C. Swift classes definitely use different method invocation semantics (unless you adorn the class with the @objc attribute).

eswick2• 12 years ago

What I meant by that was, the Objective-C runtime is still needed.

msoad• 12 years ago

If you have Xcode 6 installed this is the binary to actual Swift REPL:

    /Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift

Also try :gui command inside the REPL

pohl• 12 years ago

Give it the -i argument when you invoke it and you can use it for a #! shell

micampe• 12 years ago

Don't run the binary directly, that path will change when the GM ships. Use:

    xcrun swift

itsbits• 12 years ago

I am getting DB error

eswick2• 12 years ago

/me buys more RAM.

tempodox2• 12 years ago

In other news, the computer serving the article has evaporated due to overheating. By browser almost died.

TazeTSchnitzel• 12 years ago

Interesting. So Swift's speed stems from not doing things the Objective-C way.

How well does compatibility fare?

mtabini• 12 years ago

I think Apple has been clear that much of the underlying mechanics of Swift remain tightly coupled with the ObjC runtime, which makes sense if you think that Swift code must interoperate with all the existing Cocoa and Cocoa Touch frameworks and third-party code written in Objective-C (thus also allowing Apple to hedge its bet in case Swift tanks with developers).

What's _really_ going to be interesting going forward is whether Apple introduces new features in the runtime that are only available to Swift code, or whether it starts making change to the runtime that favour Swift over Objective-C—and that's probably going to tell us when the latter is to be considered a legacy language.

Inside Swift

Related Stories