Go语言指针类型字段赋值简写方式及代码简化方法咨询

Great question! You're right that declaring a separate variable just to take its address feels unnecessary—there are cleaner ways to assign a pointer field in Go. Let's walk through a couple of practical options depending on your Go version:

1. Directly take the address of a literal (Go 1.17+) #

Starting in Go 1.17, you can take the address of a composite literal directly, which lets you skip the intermediate variable entirely. This is the most concise and readable approach for modern Go:

package main
import "fmt"

type test struct {
    A *int
    B string
}

func main() {
    // Option A: Initialize the struct all at once
    A := test{
        B: "hello",
        A: &int{1}, // No separate x variable needed!
    }
    fmt.Printf("%s, %v", A.B, *A.A)

    // Option B: Assign fields individually if you prefer
    // var A test
    // A.B = "hello"
    // A.A = &int{1}
}

2. Use the new function (compatible with all Go versions) #

If you need to support older Go versions (pre-1.17), the new function allocates memory for a type and returns a pointer to it. You can then assign the value directly to the dereferenced pointer:

package main
import "fmt"

type test struct {
    A *int
    B string
}

func main() {
    var A test
    A.B = "hello"
    A.A = new(int) // Allocates an int and returns a *int
    *A.A = 1       // Set the value of the int the pointer points to
    fmt.Printf("%s, %v", A.B, *A.A)
}

3. Compact temporary variable (if you prefer) #

If you still want to use a temporary variable but keep it tight, you can declare and assign it in a single line (though this is slightly less clean than the first two options):

package main
import "fmt"

type test struct {
    A *int
    B string
}

func main() {
    var A test
    A.B = "hello"
    x := 1; A.A = &x // Single-line declaration and address assignment
    fmt.Printf("%s, %v", A.B, *A.A)
}

For most cases, the first option (&int{1}) is the best choice—it's clean, avoids clutter, and aligns with modern Go idioms.

内容的提问来源于stack exchange，提问作者heretolearn