如何用扫描值填充切片

Question

I'm brand new to Go and having trouble getting fmt.scan() to fill a slice. The number of input values is dynamic and I can't use a for loop. My initial thought was to try this:

package main

import "fmt"

func main() {
    var x []int
    fmt.Println("Enter input")
    fmt.Scanf("%v", append(x))
    fmt.Println(x)
}

Which obviously doesn't work. Can someone point me in the right direction?

Answer 1

[Get] fmt.Scan() to fill a slice. The number of input values is dynamic and I can't use a for loop.

---

Perhaps, something like this:

package main

import "fmt"

func input(x []int, err error) []int {
    if err != nil {
        return x
    }
    var d int
    n, err := fmt.Scanf("%d", &d)
    if n == 1 {
        x = append(x, d)
    }
    return input(x, err)
}

func main() {
    fmt.Println("Enter input:")
    x := input([]int{}, nil)
    fmt.Println("Input:", x)
}

Output:

Enter input:
 1
2 3
4
 5  6  7

Input: [1 2 3 4 5 6 7]

---

ADDENDUM:

When storage is allocated for a variable or a new value is created, and no explicit initialization is provided, the variable or value is given a default value, the zero value for its type: nil for slices. Conversions are expressions of the form T(x) where T is a type and x is an expression that can be converted to type T. []int(nil) is a conversion to the zero value for the slice value []int.

x := input([]int(nil), nil)

is equivalent to

x := input([]int{}, nil)

or

var x []int
x = input(x, nil)

I have revised my answer to use:

x := input([]int{}, nil)