Microsoft Releases .NET 11 RC1 with Go-Live Support, C# 15 and F# 11 as Default Language Versions

InfoQ Homepage News Microsoft Releases .NET 11 RC1 with Go-Live Support, C# 15 and F# 11 as Default Language Versions

Release Candidate 1 makes C# 15 the default language version for projects that target .NET 11. According to the C# release notes, the version stabilizes the features added during the preview cycle, including collection expression arguments, union types, non-virtual static interface members, closed class hierarchies, labeled break and continue, and extension indexers.

Union types no longer require the preview language setting. Roslyn now uses the final CSharp15 names, and a new API exposes the cases of a union to analyzers. Unsafe Evolution stays a preview feature with its own flag, and RC1 allows await inside an unsafe context.