In object-oriented systems, we often need to perform different operations on complex data structures. If the operation logic is embedded directly inside the data structure, it will not only increase the complexity of the class, but also make the code difficult to maintain and expand. The Visitor Pattern provides an elegant way to define new operations for these structures by separating operations from data structures. This article will introduce the concept of the Visitor Pattern in detail, the difference from other patterns, the problems it solves, and implementation examples in Golang...