[Proposal]: Top-level members

[jjonescz]

Top-level members

• Specification: Add top-level members proposal #9719
• Discussion: Top-level members #9802

Summary

Allow some members (methods, operators, extension blocks, and fields) to be declared in namespaces
and make them available when the corresponding namespace is imported.

// util.cs
namespace MyApp;

void Print(string s) => Console.WriteLine(s);

string Capitalize(this string input) =>
    input.Length == 0 ? input : char.ToUpper(input[0]) + input[1..];

Design meetings

• LDM 2025-08-18