Avoiding Type Assertions in Interface Handling

When working with interfaces in Go, it can become tedious to perform type assertions multiple times, especially when the interface is used in various locations within a function. This issue poses the question of whether there is a way to create a variable of the desired type once and utilize it throughout the function.

Go's statically typed nature and the absence of generics make it impossible to directly implement the desired solution. However, alternative approaches exist:

1. Abstraction via Interface:

Design an interface that encapsulates the common functionality you wish to apply to different structs. Implement this interface in your concrete types. Assigning a variable of this interface type to data will eliminate the need for type assertions or switches.

2. Reflection:

Leverage reflection to access common fields identified by their names. While this provides no compile-time guarantees, it allows you to interact with fields dynamically. For an example, refer to this question: "Assert interface to its type."

Note: Implementing the interface approach is more efficient and results in cleaner code. Nevertheless, reflection remains a potential option in certain scenarios.