err.go

package main

import "fmt"

type SomeError struct { string }
var err *SomeError

func (x *SomeError) Error()string { return x.string }

func MaybeLog(err error) {
  if err != nil {
    fmt.Printf("MaybeLog Error: %v %T\n", err, err)
  }
}
func main() {
  if err != nil {
    fmt.Printf("Main Error: %v %T\n", err, err)
  }
  MaybeLog(err)
}
/** Output:
MaybeLog Error: <nil> *main.SomeError
**/