[Proposal]: Target-typed generic type inference

[MadsTorgersen]

Target-typed generic type inference

• Specification: https://github.com/dotnet/csharplang/blob/main/proposals/target-typed-generic-type-inference.md
• Discussion: {Discussion]: Target-typed generic type inference #9628

Summary

Generic type inference may take a target type into account. For instance, given:

public class MyCollection
{
    public static MyCollection<T> Create<T>() { ... }
}
public class MyCollection<T> : IEnumerable<T> { ... }

We would allow the Create method to be called without type argument when it can be inferred from a target type:

IEnumerable<string> c = MyCollection.Create(); // 'T' = 'string' inferred from target type

Design meetings

• https://github.com/dotnet/csharplang/blob/main/meetings/2025/LDM-2025-08-18.md#type-inference
• https://github.com/dotnet/csharplang/blob/main/meetings/2025/LDM-2025-08-20.md#target-type-inference-improvements