Declaring variables in Go

Question

The Go documentation indicates one should use the shorthand:

x := "Hello World"

as opposed to the long form

var x string = "Hello World"

to improve readability. While the following works:

package main   
import "fmt"
var x string = "Hello World"
func main() {
    fmt.Println(x)
}

This does not:

package main
import "fmt"
x := "Hello World"
func main() {
    fmt.Println(x)
}

and gives the error "non-declaration statement outside function body". If instead I declare it within the function:

package main
import "fmt"
func main() {
   x := "Hello World"
   fmt.Println(x)
}

Then it works just fine. It seems I can only use the shorthand within the function that uses the variable. Is this the case? Can anyone tell me why?

+Charlie Thanks for the link to the specs. If you write this as an answer, I'll accept it. — ridthyself, Oct 15 '14 at 17:38
possible duplicate of [Why isn't short variable declaration allowed at package level in Go?](http://stackoverflow.com/questions/18854033/why-isnt-short-variable-declaration-allowed-at-package-level-in-go) — JimB, Oct 15 '14 at 18:56

Charlie Tumahai · Accepted Answer · 2014-10-15T19:32:29.437

5

With this restriction, everything at package level begins with a keyword. This simpflies parsing.

edited Oct 15 '14 at 19:32

answered Oct 15 '14 at 17:42

Charlie Tumahai

1 Answers1