A Eulogy for Objective-C

https://realm.io/news/altconf-aaron-hillegass-eulogy-for-objective-c/

by AlexeyBrin • 11 years ago

125 75 11 years ago

realm.io

fleitz7• 11 years ago

Read the eulogy when the base libraries are Swift...

When swift code that interacts with the base libraries is faster, and when swift code compiles faster.

Swift so far is a language that over promises and under delivers...

morqon4• 11 years ago

I'm not sure, I've had great fun learning it, and writing it is usually really nice. Sure, there have been pains along the way, but the Apple engineers are doing an amazing job with evolving Swift, intelligently, and very quickly. It is the future, and for many developers I know, it is already part of the present.

jjtheblunt• 11 years ago

How is it not an Apple spin on, say, Scala? Seems similar.

fleitz7• 11 years ago

It's certainly gotten much better with Swift 2.0, it feels like Apple finally tried to build an app with Swift 2.0 and fixed a lot of the stuff that is horribly broken.

saurik• 11 years ago

Yeah... I'm pretty certain the only code in iOS 9 that is written in Swift is the Calculator app, which was also the first app I remember Apple shipping that actually used their public version of UIKit; until iOS 4, when Apple dogfooding their library finally made UIKit "good", Apple was still using the as-yet-much-better private UIKit they had written for iOS 1 that shared very little... it even had its own UIScrollView called UIScroller and its own UITableView called UITable. While I'm sure the language keeps getting better as people provide feedback, the product isn't going to move past that "omg this is amazing" threshold until Apple dogfoods it, and until then Apple is just using everyone as guinea pigs ;P.

FWIW, I think Apple can't ship any base libraries that uses Swift until they finish ABI-compatibility, as they need to be working off the same base Swift runtime as the apps that would run against those libraries. Given that for the last year people have been shipping apps that link against an old-and-incompatible Swift runtime that Xcode bundles into your app, and given how the runtime is "intrusive" (putting stuff into the global Objective-C namespace, for example), it isn't even clear yet (so this may require more time on their end to build out more infrastructure) how they will be able to pull that off without saying "all Swift apps developed before now need to be reshipped or they will stop working on iOS 10".

artmageddon• 11 years ago

Oh goodness. Having written some small apps in both Objective-C and Swift, I'm not even sure which language I should jump back into when I want to pick it up again.

simscitizen• 11 years ago

FWIW, I think Apple can't ship any base libraries that uses Swift until they finish ABI-compatibility

You hit the nail on the head here. Until the ABI is finalized, Apple can't ship dynamic libraries to developers that are written in Swift. Swift won't be ready to fully replace Obj-C until this happens.

tempodox7• 11 years ago

... until then Apple is just using everyone as guinea pigs.

Exactly. I'm not being judgemental about that, but I don't see myself wanting to invest time into being a guinea pig. If Apple wants to build a tool that only works in and for their walled garden, I won't donate any work to it.

cageface• 11 years ago

I've been working on a medium-sized Swift 1.2 app for the last few months and, while it's come a long way from 1.0, I still don't think I'd recommend it for new work yet. Compile times are agonizingly long, even worse than C++.

chc4• 11 years ago

For anyone who isn't familiar, Aaron is one of the most venerable Objective-C programmers out there. He worked at NeXT in the '90s and has been teaching new Objective-C programmers since OS X was released.

noobthenoon• 11 years ago

I really miss the dynamic features of objective c in swift. Writing a JSON mapper or serializer is really simple if you learn the run time.

You can't do that in swift.

Objective C was a compromised version of small talk. And swift is a compromised version of a true modern language.

I'd much prefer a non compromised small talk.It's better for medium size mobile apps.

And until the rest of the libraries are in swift it doesn't feel very different.

It's like you're writing Python but you're forced to use Java libraries and Java style apis.

I hope apple doesn't ram it down our throats. Well their own frameworks depend on its dynamism and In many ways in my limited opinion objective c is better for developer happiness.

fleitz7• 11 years ago

Yup, ObjC is light and scripty. Whenever you don't like what it's doing you just make it do what you want, categories, cast to id, swizzling, respondsTo, NSSelectorFromString, etc, and when it's too slow you write those functions in C/C++ which it integrates well with.

Swift you're always contorting yourself to express things in a way that the language wants, it reminds me of writing java, it worships far to heavily at the altar of type safety as if type safety was a goal in and of itself.

ObjC is practical, Swift is academic.

laveur• 11 years ago

I couldn't agree more! There is a ton of things that you can do with the run time that just doesn't seem possible in swift.

Alphasite_• 11 years ago

That seems the opposite, very few things need those dynamic features and those that do can be special cased, which makes Objc the more pure but equally more academic language to me.

jimbokun• 11 years ago

"I'd much prefer a non compromised small talk.It's better for medium size mobile apps."

Sounds like RubyMotion.

interpol_p• 11 years ago

I initially had the same complaints about moving to Swift, especially with regards to dynamically created objects.

However I have found benefit in having strict model types that my JSON data must map into — or else cause compiler errors. I far prefer to pick up problems up at compile time then learn about them at run time.

thewarrior• 11 years ago

Also the agonisingly long compile times.

jasode2• 11 years ago

FYI for those who prefer to watch videos at faster speeds.

Instead of realm.io, I went to the youtube url instead:

https://www.youtube.com/watch?v=2s7UR-rNFss

The notes say: "THIS VIDEO IS NOT MEANT TO BE WATCHED ON ITS OWN. We went to great pains to synchronize it with the speaker’s slides,"

Well, the embedded youtube at realm.io only allows speed of 1.5x.

The direct youtube url has the speed option for 2x, so I watched it there. However, before I saw it, I spent a few seconds to flip through the slides to get an idea of what Aaron was speaking to.

morqon4• 11 years ago

It's pretty nice though, having the slides synchronised to the video. And on realm.io, below the video, there's a transcript with linked resources :)

jasode2• 11 years ago

The text below was simply excerpts instead of the full transcript. The incomplete excerpts looked like snippets of context to guide people to the middle parts of the video. You actually had to watch/listen to the video to get the full text.

For example, at the beginning, he says the word "tricycle" and when I searched for that word, it wasn't in the text below. That's when I knew it wasn't a full transcript.

fithisux• 11 years ago

One question. Why IOKit was not written in ObjC?

adamnemecek2• 11 years ago

ObjC has a pretty beefy (and therefore somewhat slow) runtime which is an issue for kernel stuff.

speeder• 11 years ago

Or explaining this better:

The objects of ObjC work very differently than C++ objects.

In Obj-C for example, there are no "methods" like C++, in C++ when you put a method in a class, (although implementation details may vary) it works like a function pointer in a C struct, and calling that method is just executing whatever code that pointer points to.

In Obj-C in contrast, to call a function of a class, you actually pass a message, that first must be interpreted, then the runtime that interpreted the message find the correct function definition to use and run.

For most apps people don't care about this, but game developers for example frequently make iOS and Mac games that in time-critical parts use pure C or even Obj-C++ so that they can skip this messaging part (that can cause significant performance problems sometimes).

Example: yesterday I was trying to figure why a open source game I like was slowing down, I ran a profiler, and the most called function, and the one with most execution time, was a simple "GetSomeRandomVar()" for spaceships (it is a spacefight battle game), I looked in the source, and saw that every frame, every spaceship call this at least once for every other spaceship, if the spaceship has an AI it calls it many, many times, I inlined it and the code became much faster.

I am very sure that if it was a ObjC call (with messaging) it would be so slow that the original author probably would not even have uploaded that to github. (by the way, the game IS an OSX game, but the original author wisely decided to go with C++ instead of ObjC)

tempodox7• 11 years ago

Yes, but then ObjC is not designed for low-level the way C & C++ are. In fact, the design goals are practically the opposite of what C++ aims at.

mrpippy• 11 years ago

DriverKit was the NeXTSTEP 3 driver environment, and it was written in ObjC.

In old mailing lists posts (https://www.geeklair.net/~dluke/PCIdevice_tutorial.txt), Godfrey van der Linden (one of the IOKit architects) made some comments about the IOKit language choice:

  As IOKit is a child of DriverKit which was implemented in ObjC we 
  wanted to reduce the amount of work necessary to convert from one 
  space to the other, as ObjC is single inherited this was easiest for 
  most of our drivers.  At first we were going to allow multiple 
  inheritance as we ported to C++ but then we tripped over the whole 
  can of worms called 'virtual' inheritance.  We really, really didn't 
  want to turn all of our developers into C++ experts, which you have 
  to be to use virtual inheritance properly.  Another side effect is 
  that we are now reasonable language independent.  At some stage in 
  the future we may be able to move IOKit over to a good programming 
  language.

I suspect that if they had re-written IOKit in 2010, it would be in Objective-C. My guesses why it was done in C++ in 2000:

- programmer familiarity/comfort level: remember that classic Mac development was mostly being done in C/C++ by the mid-90s, and the Mac developers still around by 2000 didn't need to be given more reasons to jump ship. Carbon was created so that Mac C/C++ applications could be brought to X, and having drivers written in C++ was another easing factor.

This also includes Apple's internal development teams--I don't think all the longtime Apple teams were that bullish on NeXT technologies. Remember that the original OS X Finder was a C++ Carbon app built with CodeWarrior.

- ObjC not considered inevitable: in 2000 it was not at all clear that ObjC would be thriving for another 15+ years. The C/C++ Carbon API was one direction for the future, the Cocoa-Java bridge was another, another was putting C++-style syntax on top of ObjC (which was never completed). C++ wasn't going anywhere, whereas it would be painful to have driver development handcuffed to ObjC if applications abandoned it.

- performance: it probably would have been a non-issue, but C++ is a safer choice performance-wise.

There might be other interesting tidbits on the darwin-development or darwin-drivers if you go back to 2000/2001.

ams6110• 11 years ago

In 2000 or thereabouts there was a strong push towards Java.

masters3d• 11 years ago

No language is perfect. If a language is not grounded to solve concrete problems, then we just end up with a new c++.

"Swift is not the ultimate language, it’s not flawless, it is compromised because of Objective-C interoperability."

KSS42• 11 years ago

Blaine Guest? Typo?

glitch• 11 years ago

Yeah, I noticed that too. I told them and they fixed that typo.

waynecochran• 11 years ago

Can I blissfully go on writing OS X and iOS apps in Objective-C (I spent 15+ years training brain cells in Obj-C)? Aaron H. seems to suggest I can -- Apple isn't just pong to deprecate the entire language one morning in early June I hope. I have learned just enough Swift to read it, but not ready to invest the time to learn it well.

glhaynes• 11 years ago

You're definitely safe writing your own apps in it for well into the foreseeable future — there's not only way too much app code out there for it to be deprecated soon, but the vast majority of the system and bundled apps are in Objective-C.

I'd expect Objective-C jobs, though, to decline in number over time as Swift jobs rise. If you're doing it professionally, not learning Swift is going to increasingly limit your options, perhaps pretty rapidly — a few months ago, I got turned down for a job in part because of lack of Swift experience. Ended up landing a different job where we're writing a Swift app and step 1 for everyone on the team was "learn Swift".

Spivak• 11 years ago

However, as those Objective-C jobs decline their pay-scale will probably increase as companies desperately attempt to find someone to maintain their legacy apps.

omarforgotpwd• 11 years ago

I learned Objective-C from Aaron Hillegass's book many years ago. Pretty funny to hear from someone who still loves the language.

aidenn0• 11 years ago

Objective C: All the blazing speed of Smalltalk with the memory safety of C.

tolmasky• 11 years ago

The developments that Facebook is working on with React Native are just so much more exciting than another riff on C++. For most "utility" apps, I just don't think performance is such an issue that the point of research should be these (comparably) incredibly low level concerns.

When I see the bugs going on in iOS apps, it has to do with models that are broken for what modern programs looks like today: things like asynchronicity. Animation is still a mess to wrap your mind around when you have a series of asynchronous events (animations, loads, what have you) that are tied together, but can also be canceled half way through. This is why I can still break many apps by just tapping all over the place (or clicking all over the place: http://tolmasky.com/letmeshowyou/Yosemite/Safari%20Animation... ).

Combining the determinism of React style immediate mode drawing with JS async/await is truly exciting for app development.

Now, of course the elephant in the room is that neither of these matter that much when most the apps being written are games that will continue using C++ or Unity (if you actually care about speed these are your best bet). Especially with the work Apple is doing with Metal that will improve these platforms as well.

rimantas• 11 years ago

Oh, React, the newest silver bullet.

kybernetyk• 11 years ago

I just don't think performance is such an issue that the point of research should be these (comparably) incredibly low level concerns.

Yes. Performance maybe not. But power efficiency is. If your mobile app is bloated and takes more resources than needed to perform its task then you're wasting the user's battery.

tempodox7• 11 years ago

ObjC is far from dead for me. And it will take Swift a long time (if ever) to deliver what ObjC can do.

Swift is not completely bad per se, but it's far from being as approachable as C. In C, you only need to read all the header files, then you “know everything”. In Swift, there aren't even any files with declarations you _could_ read. But then, a completely obscure language seems like a perfect fit for a walled garden.

johndpope• 11 years ago

If I didn't have so much code in objective-c - I'd welcome the passing. Until then - I've built a project to migrate objective-c code > swift en masse. check out http://objc2swift.io for hockeyapp download.

kerusan• 11 years ago

Awsome speach! When Apple dumped Objective-C in WebObject we at OOPS printed a TShirt that we showed the crouds at WWDC. I can only repeat now what it read. [objC retain] Kerusan, OOPS, Sweden

A Eulogy for Objective-C

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