问题
Case A Not following the Getter & Setter convention
human/human.go
package human
type Human interface {
GetName() string
SetName(name string)
}
type Person struct {
Name string
}
func (p Person) GetName() string {
return p.Name
}
func (p *Person) SetName(name string) {
p.Name = name
}
main/main.go
package main
func main() {
john := Person{Name:"john"} // Uppercase Fields are visible
fmt.Println(john)
}
Case B Following getter and setter convention
package human
type Human interface {
Name() string
SetName(name string)
}
type Person struct {
name string
}
func (p Person) Name() string {
return p.name
}
func (p *Person) SetName(name string) {
p.name = name
}
main/main.go
package main
func main() {
john := Person(name: "John") // lowercase name is not visible outside the package
}
The problem with following convention is that I can't instantiate the struct while providing its field names. I'd like to use the convention but I am stuck with the private access.
回答1:
When instantiating a structure (or object, in object oriented languages), you should not specify the value of private fields anyway. It can make sense, however, to provide data that may end up in private fields, or be treated in a completely different manner. In this case, OOP warrants the use of a constructor, and the Go convention is a to provide a fuction called New[YourStructure].
func NewPerson(name string) Person {
return Person{name: name}
}
In this trivial example, the name is simply copied to the private field, but in a more complex example, other operations could take place (e.g. checking that the name is valid, or looking up the name and taking action depending on the result…).
来源:https://stackoverflow.com/questions/42739877/getter-and-setter-conventions-in-go-lang