Lowering in C#: What's really going on in your code? - David Wengier

[@keja0]

This guy was awesome, good presentation, clear talking and interesting subject.

[@sau002]

Good presentation. I like the simplistic approach.

[@christofstanits]

excellent talk!

[@alexeski4109]

Amazingly insightful talk.

[@Iregger0]

Shouldn't that while loop @1:26 translate to something like again: if(something) dostuff i++ goto again; ? Now it (@1:31) looks more like do while Anyway, good stuff. Thanks.

[@MobilTemp]

Great stuff

[@lollo4711]

Enumerator: Removing items from the list (from inside the loop) will make MoveNext() return/set a false Current()-Item?!

[@kevin179887]

Was the compiler mentioned that this talk referenced? There are many C# compilers and they operate differently.

[@zombie_pigdragon]

At 36:00, he links to roslyn, which is the C# compiler that he used.

[@TheLbadwal]

Gold, many thanks!

[@theMagos]

18:28 (e as IDisposable)?.Dispose();

[@keja0]

Not in the code he has shown, bc that was C# 4. Null-conditional operators are only after C# 6

[@emmepombar3328]

Ah, your code is before lowering. 😀

[@bbcskych4]

Why there will be a stackoverflow exception in c#4's foreach ?

[@merthsoft]

I believe he was referring to the website stackoverflow, because there were a LOT of questions about this behavior when C#4 came out.

[@rohithnaik123]

Very Confusing and unclear :(

[@slavaknyazev45]

which part?

[@rohithnaik123]

@@slavaknyazev45 I feel like the speaker's ordering of topics was off. He should look into reformatting his talk to make it more intuitive and flowing. I had to watch this 3 times and then I got the entire thing.

[@rohithnaik123]

I just want to add that the talk was very informative if you give it some time. The Sharplab demo was really cool as well. I think he should have used that in the beginning to make the intent of the video pop.

[@anantmishra6783]

dead boring but useful. D:

[@payamism]

If you are concerned about performance to this low level, then C# is the wrong tool for the job. Go use C++, C, Rust...

[@merthsoft]

Yes, this is all great stuff to know, but I don't think it's good to know for optimization reasons. If my manager told me that code chunk he showed at 33:35 was too slow or used too much memory I'd look at him concerned and then I'd profile it before doing any analysis about what the compiler is doing.

[@mzg147]

I am just concerned how my code really works.

[@comradestinger]

I mean.. C# *is* used for some high-performance stuff, like in unity for games or other desktop workloads. Knowing which abstractions are cheap and which ones create their own classes and statemeachines (omg) I think is really good so you don't accidentally use them in hot paths.

[@Robert-G]

Comrade Stinger the state machine isn’t the problem, that’s equivalent to an int state and a switch. The problem is, that it needs a class, and everything that allocates can trigger a „whole world stops GC sweep“

[@ZahrDalsk]

@@comradestinger C#? Well that explains why unity's performance is so famously bad.

[@UPSCCSE-ku7ej]

He is confused