A Tour of Go If and else

Variables declared inside an if short statement are also available inside any of the else blocks.

package main  

import (
    "fmt"
    "math"
)

func pow(x, n, lim float64) float64{
    if v := math.Pow(x, n); v < lim {
        return v
    } else {
        fmt.Printf("%g >= %g\n", v, lim)
    }
    //can‘t use v here, though
    return lim

}
func main() {
    fmt.Println(
        pow(3, 2, 10),
        pow(3, 3, 20),
        )

}