41 lines
622 B
Go
41 lines
622 B
Go
package main
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import "fmt"
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type Reader interface {
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ReadBook()
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}
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type Writer interface {
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WriteBook()
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}
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// 具体类型
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type Book struct {
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}
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func (this *Book) ReadBook() {
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fmt.Println("Read a Book")
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}
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func (this *Book) WriteBook() {
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fmt.Println("Write a Book")
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}
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func main() {
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// b: pair<type: Book, value: book{}地址>
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b := &Book{}
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// r: pair<type: , value: >
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var r Reader
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// r: pair<type: Book, value: book{}地址>
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r = b
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r.ReadBook()
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var w Writer
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// r: pair<type: Book, value: book{}地址>
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w = r.(Writer) // 此处的断方为什么会成功？因为w r的具体type是一致的
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w.WriteBook()
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}
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