Can you describe the main components that make up the error structure?

In Go, the error structure typically includes the following main components:

• Error message — a string describing the essence of the error.
• Error type — often implemented through custom types that implement the error interface. This allows distinguishing errors by type.
• Wrapped errors — errors can contain other errors to preserve the chain of causes (for example, using fmt.Errorf("%w", err)).
• Stack trace — not built into the standard error, but can be added using third-party libraries for debugging.

Example of a custom error with additional fields:

package main
import (
    "fmt"
)

type MyError struct {
    Msg  string
    Code int
}

func (e *MyError) Error() string {
    return fmt.Sprintf("Error %d: %s", e.Code, e.Msg)
}

func main() {
    err := &MyError{Msg: "something went wrong", Code: 500}
    fmt.Println(err.Error())
}