pair<type:, value:>
例:
var a string
//pair<type:string,value:"abc">
a = "abc"
package main
import "fmt"
type Reader interface {
ReadBook()
}
type Writer interface {
WriteBook()
}
// 具体类型
type Book struct {
}
func (b *Book) ReadBook() {
fmt.Println("Read a Book")
}
func (b *Book) WriteBook() {
fmt.Println("Write a Book")
}
func main() {
// b: pair<type:Book, value:book{}地址>
b := &Book{}
// r: pair<type:, value:>
var r Reader
// r: pair<type:Book, value:book{}地址>
r = b
r.ReadBook()
// w: pair<type:, value:>
var w Writer
// w: pair<type:Book, value:book{}地址>
// 此处的断言为什么会成功?因为w r 具体的type是一致的,所以会断言成功
w = r.(Writer)
w.WriteBook()
}
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