Where is System.UInt128?

[HSchwichtenberg]

Description

According to https://learn.microsoft.com/en-us/dotnet/api/system.uint128?view=net-7.0 and dotnet/core#7454 there is a new type public readonly struct UInt128 in the System namespace

However, with
System.UInt128 x;
I get the error
The type or namespace name 'UInt128' does not exist in the namespace 'System'
when running dotnet build

Configuration

.NET 7.0.100-rc.1.22431.12

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Issue Details

---

Description

According to https://learn.microsoft.com/en-us/dotnet/api/system.uint128?view=net-7.0 and dotnet/core#7454 there is a new type public readonly struct UInt128 in the System namespace

However, with
System.UInt128 x;
I get the error
The type or namespace name 'UInt128' does not exist in the namespace 'System'
when running dotnet build

Configuration

.NET 7.0.100-rc.1.22431.12

Author:	HSchwichtenberg
Assignees:	-
Labels:	area-System.Numerics, untriaged
Milestone:	-

[stephentoub]

Configuration
.NET 7.0.100-rc.1.22431.12

What does your csproj look like?

[HSchwichtenberg]

I found the problem: I still had a PackageReference to System.Runtime.Experimental.
After removing that, System.Int128 is available!

Sorry for disturbing you with the question I could have answered myself 🤯

[stephentoub]

Glad you got it sorted out.