Go Unpacking Array As Arguments

go argument-unpacking
eatonphil picture eatonphil · Jul 9, 2013 · Viewed 66.2k times · Source

So in Python and Ruby there is the splat operator (*) for unpacking an array as arguments. In Javascript there is the .apply() function. Is there a way of unpacking an array/slice as function arguments in Go? Any resources for this would be great as well!

Something along the lines of this:

func my_func(a, b int) (int) {
    return a + b
}

func main() {
    arr := []int{2,4}
    sum := my_func(arr)
}

I do apologize if I'm making an syntactical/assorted mistakes. I'm new to Go.

Answer

Hunter McMillen picture Hunter McMillen · Jul 9, 2013

You can use a vararg syntax similar to C:

package main
import "fmt"

func my_func( args ...int) int {
   sum := 0
   for _,v := range args {
      sum = sum + v
   }

   return sum;
}

func main() {
    arr := []int{2,4}
    sum := my_func(arr...)
    fmt.Println("Sum is ", sum)
}

Now you can sum as many things as you'd like. Notice the important ... after when you call the my_func function.

Running example: http://ideone.com/8htWfx

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