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loading story #48249178
superjan | parent | next
What you can do in C# today is convert any unsafe pointer to Span whenever you get your hands on it, and pass around slices. You can still drop down to ‘fixed’ when it turns out you need it for performance.
pjmlp | parent | next
Most likely a side effect related to Windows team finally giving some C# love, instead of COM and C++, given the comparisons between C# 16 with Rust and Swift in a few article sections.
moomin | parent
The Windows team is talking to DevDiv again? Satan's putting on his ice skates right now.
pjmlp | root | parent
One can only hope.

C++/WinRT is in maintenance, and you will notice the WinUI 3.0 does most of their demos, and gallery with C#.

loading story #48249213
caspper69 | parent | next
They are aligning more closely with the Rust 2024 model for unsafety, which requires inner annotations at the point of unsafety in addition to notation of the function (unless it is the safe-unsafe boundary) plus it imposes a requirement for a SAFETY doc notation for describing the specific invariants the caller must enforce to uphold the safety guarantees. Not terribly onerous in my opinion. I maintain a few native library wrappers on nuget, so I will have to do some updates around IntPtr usage, but this doesn’t seem like it will be terribly painful in my case. Thankfully I don’t do much marshalling. Plus you get a nifty badge on nuget for making your library safe.

The blurb toward the end about Rent/return makes me a bit nervous though. They say they’re not going full borrow checker, but rent at least sounds an awful lot like borrow to me. Details were basically non-existent though.

I guess I wonder what the end game is here though. The more they make C# like Rust with a GC, the less incentive people have to use C# except maybe to support legacy work. I am still far more comfortable in C# than Rust, and I believe C# is superior for e.g. web, but over time this advantage could be lessened quite a bit as the Rust ecosystem continues to grow.

SideburnsOfDoom | parent
> The unsafe keyword is being redesigned

OK, I see a lot of C# code often and over a long time.

I see the "unsafe" keyword used approximately never.

I'm sure that this is useful for some cases. But not everyday things for most of us. If we did use it, it would be carefully isolated in a library for a specific purpose.

tialaramex | parent | next
This moves C# to a more modern systematic understanding of what this keyword is for, but it'll remain very rare in C# the same way it's rare in Rust, and presumably in Swift.

The choice of keyword "unsafe" is partly psychological. Turns out if you called this exact same feature "trusted" or whatever the programmers don't have the appropriate feelings about it. They want to write trusted code, they don't want to write unsafe code, so making them write the keyword "unsafe" provides that psychological disincentive.

pixl97 | root | parent
Initialize liveHandgrenade;
zmj | parent | next
There are standard library APIs that let you do memory-unsafe things without the unsafe keyword (CollectionsMarshal, MemoryMarshal). They're useful, but the burden is on the caller to uphold the invariants. This proposal seems aimed at making that kind of contract more explicit and obvious.
pjmlp | parent | next
Many of us use it in scenarios where others would write a blog post about a rewrite in Rust, C++ or whatever.

CLR was designed to support languages like C++, yet many don't learn the knobs.

Quothling | parent | next
Around here C# is only really used at stagnant middle sized companies with horrible code bases. The sort where the company follow Uncle Bob religiously, while completely misunderstanding everything Uncle Bob ever said. Doesn't mean the language (and it's runtime) can't be good.
Profan | parent | next
In a game development context, especially where C++ interop is involved and a lot of code lives across a boundary where memory is owned by C++ but you want to avoid/minimize marshaling overhead or just generally maximize performance, the unsafe keyword is quite handy, but outside of those you can indeed probably get around by approximately never using it.

There's a lot of power C# gives you if carefully curated, making a lot of cases where people previously might have seen C++ as the only option as suddenly quite viable.

... See also the somewhat arcane Unsafe.As etc APIs

smt88 | parent
C# is like Rust in the sense that a regular (web, desktop, etc.) developer probably won’t need unsafe, but it’s useful for lower-level work in libraries and CLI tools, especially where performance is important.