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C# 9 top-level programs and target-typed expressions

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Re: C# 9 top-level programs and target-typed expressions

#121

Post by zwieback »

binarynate wrote: post #103
zwieback wrote: post #15

Earlier quoted context omitted.

C# is my goto for Windows, for sure. Is the native interop good in Linux as well? I've never even considered anything like that, would probably gravitate to C++ since that's what I'm familiar with but would seriously consider Go or Java in non-Windows situations.

Yes, native interop works the same across all platforms (Linux, macOS, Windows, Android, iOS). You can just place a dynamic library with C linkage (.so, .dylib, or .dll file) into your app's folder, and then you can call the native functions as external functions in C#. For example, if your library exports the following C function: void printMessage(char *message) { printf("Message from C#: %s", message) } You can ca…

Thanks, I'll give it a try. I've done a lot of interop in Windows so it'll be good to leverage to Linux.

Re: C# 9 top-level programs and target-typed expressions

#122

Post by osigurdson »

FridgeSeal wrote: post #100

> Top-level programs allow you to write the main method of your application without having to add a class with a static Main method Riveting stuff happening in .Net land! Sarcasm aside, this seems like such a small, oddly-specific, once-off feature that its like...why bother? Any C# devs want to enlighten me here?

The original post is here: https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/csh....

Re: C# 9 top-level programs and target-typed expressions

#123

Post by bkuehl »

xbar wrote: post #73
bob33212 wrote: post #54

Earlier quoted context omitted.

They were created by the same person. https://en.m.wikipedia.org/wiki/Anders_Hejlsberg All the hate C# gets is because of balmer and gates, not for technical reasons

Are you sure? My personal reluctance to C# has been that it's not handy for the stuff I do that needs to run on Windows, Mac, and Linux, which is everything.

.net core has handled that well in the last ~3-5 years. Yeah, not a great rep before that but the new iteration/rewrite has been impressive.

Re: C# 9 top-level programs and target-typed expressions

#124

Post by ygra »

DaiPlusPlus wrote: post #72
gnud wrote: post #43

Earlier quoted context omitted.

You could create tuples with `Tuple.Create("a", 1)` since at least .NET 4, if not 3. Since C# 7 you can also create tuples using just `("a", 1)`. But tuples are not KeyValuePairs. So the new "new" syntax will be very helpful in a lot of cases.

I really don't understand why they haven't added implicit conversion operators between the modern ValueTuple and the legacy value-types like KeyValuePair, Tuple, and Pair, grumble. It's a non-breaking change!

Tuple is not a value type. And this means that they won't add an implicit conversion, because right now a major focus of .NET and C# is also performance. and this conversion would mean an implicit heap allocation. They'd rather avoid adding features of this sort as I understand it.

Re: C# 9 top-level programs and target-typed expressions

#125

Post by johnfn »

FridgeSeal wrote: post #101
gameswithgo wrote: post #99

Earlier quoted context omitted.

top level is mostly going to be nice when teaching new programmers. You can just get on with hello world and now have to type all this boiler plate and explain why you have to. But yeah, for "real" programs it is probably irrelevant. But who knows, maybe we will find a use for it. I am mostly excited about the sort-of option type getting rid of nulls option.

> top level is mostly going to be nice when teaching new programmers. You can just get on with hello world Yeah it seems like kind of a weird thing? “Here’s marginally less boilerplate once , if someone is going to learn to use the language, they may as well learn how it actually works instead of hiding stuff that they’ll soon see anyways...

You should see how many new engineers are confused in CS101 when confronted with all of Java's boilerplate just to write a simple "hello world" program. It's a real issue.

Re: C# 9 top-level programs and target-typed expressions

#126

Post by aidenn0 »

_fqqr wrote: post #118
aidenn0 wrote: post #117

Can anyone comment on cross-platform GUI for .net? Last time I seriously investigated it, Gtk# seemed to be the primary option. Some quick googling found avalonia, but no clue if that's a reasonable GUI to use. I'm guessing MS isn't planning on porting WPF to linux (though I suppose linking with wine might work)...

It looks like MAUI [1] is the path forward [1] https://devblogs.microsoft.com/dotnet/introducing-net-multi-...

Comment streams there indicate that it relies on Xamarin.Forms which is GTK2 and does not support .NET core.

Re: C# 9 top-level programs and target-typed expressions

#127

Post by BoorishBears »

FridgeSeal wrote: post #101
gameswithgo wrote: post #99

Earlier quoted context omitted.

top level is mostly going to be nice when teaching new programmers. You can just get on with hello world and now have to type all this boiler plate and explain why you have to. But yeah, for "real" programs it is probably irrelevant. But who knows, maybe we will find a use for it. I am mostly excited about the sort-of option type getting rid of nulls option.

> top level is mostly going to be nice when teaching new programmers. You can just get on with hello world Yeah it seems like kind of a weird thing? “Here’s marginally less boilerplate once , if someone is going to learn to use the language, they may as well learn how it actually works instead of hiding stuff that they’ll soon see anyways...

This isn't a REPL but the benefits are almost identical

Good for beginners, good for removing the overhead of "trying just one quick thing real quick"

Re: C# 9 top-level programs and target-typed expressions

#128

Post by tonyedgecombe »

bkuehl wrote: post #123
xbar wrote: post #73

Earlier quoted context omitted.

Are you sure? My personal reluctance to C# has been that it's not handy for the stuff I do that needs to run on Windows, Mac, and Linux, which is everything.

.net core has handled that well in the last ~3-5 years. Yeah, not a great rep before that but the new iteration/rewrite has been impressive.

I don't think it really started to settle down until .Net Core 3.0 which is just 18 months ago. Five years ago it was version 1.0 and a bit of a dog on all platforms.

Re: C# 9 top-level programs and target-typed expressions

#129

Post by tonyedgecombe »

ziml77 wrote: post #78
thrower123 wrote: post #36

Earlier quoted context omitted.

I'm pretty sure WinForms is being migrated. I've built dotnet 5 WinForms apps, anyway. At least on Windows - I wouldn't bet on a Linux Gtk/Qt port any time soon. WPF is probably dead though.

Microsoft wouldn't let WPF die. Anyone writing enterprise desktop applications is using it heavily.

Anyone writing enterprise desktop applications is using it heavily.

I don't think there is much of that going on anymore.

In reality Microsoft did let WPF languish for years, it always felt unfinished. I was very surprised when they migrated it to .Net core.

Re: C# 9 top-level programs and target-typed expressions

#130

Post by tonyedgecombe »

will4274 wrote: post #111
FridgeSeal wrote: post #100

> Top-level programs allow you to write the main method of your application without having to add a class with a static Main method Riveting stuff happening in .Net land! Sarcasm aside, this seems like such a small, oddly-specific, once-off feature that its like...why bother? Any C# devs want to enlighten me here?

Why not bother? This mindset is one of the core features of .NET-land - Microsoft just goes ahead and implements anything useful. It's why we have a gigantic standard library ("framework") filled with every function under the sun and some multiple times. We didn't have to wait until C++20 to get string.Contains. Sometimes the features Microsoft implements are more useful than others but most of them are a little usef…

It's not without its downsides though, the language and ecosystem is quite big now. I don't envy people starting out and having to learn it all from scratch.
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