如何附加到切片指针接收器

I have a type alias for a slice. And I want to be able to append to the slice (or filter from the slice) when the slice is a pointer receiver:

package main

import (
    "fmt"
)

type itself []string

func (h itself) appendToItself(test string) {
    h = append(h, test)
}

func main() {
    h := itself{"1", "2"}
    h.appendToItself("3")
    fmt.Println(h, "<- how do I make it [1,2,3]")
}

Log:

[1 2] <- how do I make it [1,2,3]

You need to actually pass a pointer, try:

package main

import (
    "fmt"
)

type itself []string

func (h *itself) appendToItself(test string) {
    *h = append(*h, test)
}

func main() {
    h := itself{"1", "2"}
    h.appendToItself("3")
    fmt.Println(h, "<- how do I make it [1,2,3]")
}