Reflection for Dynamic Interface Implementation in Go

Reflection in Go is a powerful tool that allows for the inspection and manipulation of code at runtime. One question that has been raised is whether it's possible to use reflection to create a new function that implements a specific interface.

Problem Statement

The challenge is to use reflection to implement an interface that defines RPC-style methods. For instance, consider an interface like:

type MyService interface {
    Login(username, password string) (sessionId int, err error)
    HelloWorld(sessionId int) (hi string, err error)
}

The goal is to use reflection to implement this interface by translating method calls into RPC calls, marshaling inputs, and unmarshaling results. However, obtaining a slice of input parameters as interfaces is insufficient to dynamically create a value that implements the interface using reflection-based functions.

Solution

Unfortunately, creating a type with attached methods via reflection and instantiating an object of that type is not possible. While the unsafe package might provide some possibilities, it's an arduous and inefficient approach.

Alternatives

Instead of relying on reflection, consider exploring alternative solutions to the underlying problem. Providing more details about the specific problem you're trying to solve could help the community suggest more suitable approaches.

Recent Development

It's worth noting that Go versions 1.5 and later introduced reflect.FuncOf and reflect.MakeFunc, which offer the capability to create functions that implement interfaces dynamically. This provides a practical and efficient solution to the problem presented.