英文:
Reuse function with return type always equal to the struct that is calling that function in golang
问题
我正在尝试在Golang中做一些在Java中使用Type可以轻松完成的事情。例如：
public class MyClass<Type extends MyClass<Type>> {public Type myMethod() {// Do somethingreturn (Type) this;}}public class Test1 extends MyClass<Test1> {public String A;Test1(String A) {this.A = A;}}public class Test2 extends MyClass<Test2> {public String B;Test2(String B) {this.B = B;}}
因此，在主函数中，我可以这样做：
Test1 t1 = new Test1("hello");Test2 t2 = new Test2("world");System.out.println(t1.myMethod().A); // 输出 "hello"System.out.println(t2.myMethod().B); // 输出 "world"
我正在尝试弄清楚在Go中是否有一种类似的方法。也许可以这样做：
type test1 struct {A string}type test2 struct {B string}func (val Type) MyMethod() Type {// Do somethingreturn val}func main() {t1 := test1{A: "hello"}t2 := test2{B: "world"}fmt.Println(t1.MyMethod().A) // 输出 "hello"fmt.Println(t2.MyMethod().B) // 输出 "world"}
英文:
I'm trying to do in Golang something that would be easily done in Java with Type. For example:
public class MyClass<Type extends MyClass<Type>> {public Type myMethod() {// Do somethingreturn (Type) this;}}public class Test1 extends MyClass<Test1> {public String A;Test1(String A) {this.A = A;}}public class Test2 extends MyClass<Test2> {public String B;Test2(String B) {this.B = B;}}
So, in main I can do
Test1 t1 = new Test1("hello");Test2 t2 = new Test2("world");System.out.println(t1.myMethod().A); // Prints "hello"System.out.println(t2.myMethod().B); // Prints "world"
I'm trying to figure out if there is a way to do somethig similar in Go.
Maybe something like:
type test1 struct {A string}type test2 struct {B string}func (val Type) MyMethod() Type {// Do somethingreturn val}func main() {t1 := test1{A: "hello"}t2 := test2{B: "world"}fmt.Println(t1.MyMethod().A) // Prints "hello"fmt.Println(t2.MyMethod().B) // Prints "world"}
答案1
得分: 0
感谢JimB，我找到了一种方法。
从Go 1.18开始，支持泛型类型。
因此，在Go中，Java的MyClass将类似于以下代码：
type MyGeneric[T any] struct {self *T}func (val MyGeneric[T]) MyMethod() *T {// 做一些操作return val.self}
Java类Test1将是：
type test1 struct {MyGeneric[test1]A string}func MakeTest1(A string) test1 {answer := test1{A: A}answer.self = &answerreturn answer}
类似地，Java类Test2将是：
type test2 struct {MyGeneric[test2]B string}func MakeTest2(B string) test2 {answer := test2{B: B}answer.self = &answerreturn answer}
所以，主函数如我们所想：
t1 := MakeTest1("hello")t2 := MakeTest2("world")fmt.Println(t1.MyMethod().A) // 输出 "hello"fmt.Println(t2.MyMethod().B) // 输出 "world"
英文:
Thanks to JimB I found a way.
From Go 1.18 Generic Types are sypported.
So the Java MyClass will look something like this in Go:
type MyGeneric[T any] struct {self *T}func (val MyGeneric[T]) MyMethod() *T {// Do somethingreturn val.self}
The Java class Test1 will be:
type test1 struct {MyGeneric[test1]A string}func MakeTest1(A string) test1 {answer := test1{A: A}answer.self = &answerreturn answer}
And similarly the Java class Test2:
type test2 struct {MyGeneric[test2]B string}func MakeTest2(B string) test2 {answer := test2{B: B}answer.self = &answerreturn answer}
So the main is as we wanted
t1 := MakeTest1("hello")t2 := MakeTest2("world")fmt.Println(t1.MyMethod().A) // Prints "hello"fmt.Println(t2.MyMethod().B) // Prints "world"
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