我有以下代码：
type FWriter struct {
WriteF func(p []byte) (n int,err error)
}
func (self *FWriter) Write(p []byte) (n int,err error) {
return self.WriteF(p)
}
func MyWriteFunction(p []byte) (n int,err error) {
// this function implements the Writer interface but is not named "Write"
fmt.Print("%v",p)
return len(p),nil
}
MyFWriter := new(FWriter)
MyFWriter.WriteF = MyWriteFunction
// I want to use MyWriteFunction with io.Copy
io.Copy(MyFWriter,os.Stdin)
我想要做的是创建一个Writer接口来包装MyWriteFunction,因为它不被命名为“Write”,我不能使用它需要一个“Writer”接口的任何东西.
这个代码不会工作,因为它抱怨：
method MyWriterFunction is not an expression,must be called
我在这里做错了什么？如何将WriteF设置为MyWriteFunction？
注意：我尽可能简化了这个问题,实际上我有一个具有MyWriteFunction和一个正常写入函数的结构,所以它有点复杂…(如果有一个更好的方法来解决我的这个问题那么我很高兴听到它！)
谢谢！！
EDIT ::我注意到我的打字错误并修复它(MyWriterFunction – > MyWriteFunction)
我认为我过分简化了这个问题,误导了我原来的意图.
遵循匿名评论和peterSO类评论,我重新创建了错误,以更好地展示我的问题：
package main
import (
"fmt"
"io"
"strings"
)
type ProxyWrite interface {
Write(p []byte) (n int,err error)
SpecialWrite(p []byte) (n int,err error)
}
type Implementer struct {
counter int
}
func (self Implementer) Write(p []byte) (n int,err error) {
fmt.Print("Normal write: %v",nil
}
func (self Implementer) SpecialWrite(p []byte) (n int,err error) {
fmt.Print("Normal write: %v\n",p)
fmt.Println("And something else")
self.counter += 1
return len(p),nil
}
type WriteFunc func(p []byte) (n int,err error)
func (wf WriteFunc) Write(p []byte) (n int,err error) {
return wf(p)
}
func main() {
Proxies := make(map[int]ProxyWrite,2)
Proxies[1] = new(Implementer)
Proxies[2] = new(Implementer)
/* runs and uses the Write method normally */
io.Copy(Proxies[1],strings.NewReader("Hello world"))
/* gets ./main.go:45: method Proxies[1].SpecialWrite is not an expression,must be called */
io.Copy(WriteFunc(Proxies[1].SpecialWrite),strings.NewReader("Hello world"))
}
我希望澄清我第一次尝试提出的意思.
有什么想法吗？
你的代码中有一个打字错误,但是将func包装到一个结构体中也是不必要的.相反,您可以定义一个包装函数的WriteFunc类型,您可以定义Write方法.这是一个完整的例子.
package main
import (
"fmt"
"io"
"strings"
)
type WriteFunc func(p []byte) (n int,err error) {
return wf(p)
}
func myWrite(p []byte) (n int,err error) {
fmt.Print("%v",nil
}
func main() {
io.Copy(WriteFunc(myWrite),strings.NewReader("Hello world"))
}