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How can I pass a slice as a variadic input?

Submitted by: @import:stackoverflow-api··
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inputhowslicevariadiccanpass

Problem

I have a function func more(... t). I'm wondering if it's possible to use a slice to populate a list of arguments ... .

I'm trying to solve the following program. Basically to mimic a normal shell which receives the command as a string.
Command function requires a "list" of arguments and I don't see how I can convert a string into a such list

import "os/exec"
import "strings"
func main(){
    plainCommand  := "echo hello world"
    sliceA := strings.Fields(plainCommand)
    cmd := exec.Command(sliceA)
}

Solution

The Go Programming Language Specification


Passing arguments to ... parameters


If f is variadic with final parameter type ...T, then within the
function the argument is equivalent to a parameter of type []T. At
each call of f, the argument passed to the final parameter is a new
slice of type []T whose successive elements are the actual arguments,
which all must be assignable to the type T. The length of the slice is
therefore the number of arguments bound to the final parameter and may
differ for each call site.


Package exec


func Command

func Command(name string, arg ...string) *Cmd




Command returns the Cmd struct to execute the named program with the
given arguments.


The returned Cmd's Args field is constructed from the command name
followed by the elements of arg, so arg should not include the command
name itself. For example, Command("echo", "hello")

For example,

package main

import (
    "fmt"
    "os/exec"
)

func main() {
    name := "echo"
    args := []string{"hello", "world"}
    cmd := exec.Command(name, args...)
    out, err := cmd.Output()
    if err != nil {
        fmt.Println(err)
    }
    fmt.Println(string(out))
}


Output:

hello world

Code Snippets

func Command(name string, arg ...string) *Cmd
package main

import (
    "fmt"
    "os/exec"
)

func main() {
    name := "echo"
    args := []string{"hello", "world"}
    cmd := exec.Command(name, args...)
    out, err := cmd.Output()
    if err != nil {
        fmt.Println(err)
    }
    fmt.Println(string(out))
}
hello world

Context

Stack Overflow Q#23723955, score: 150

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