How to Use Anonymous Structs in Go

Anonymous structs in Go are defined inline using the struct{} syntax without a preceding type name, allowing you to create temporary or one-off data structures. You declare them by listing fields directly inside the curly braces, optionally with tags, and initialize them using the same literal syntax.

// Define and initialize an anonymous struct inline
user := struct {
    Name  string
    Email string
}{
    Name:  "Alice",
    Email: "alice@example.com",
}

// Access fields directly
fmt.Println(user.Name)

// Use in function arguments or return values
func greet(u struct{ Name string }) {
    fmt.Println("Hello", u.Name)
}
greet(user)

An anonymous struct is a custom data container you define right where you need it, without giving it a permanent name. It works like a named struct but is useful for quick, one-time groupings of data, like passing a few related values to a function without creating a separate type definition. Think of it as a temporary box you build on the spot to hold specific items, rather than a reusable box you keep in your toolbox.