如何定义返回地图的函数

I am attempting to define a function which returns an initialized map:

package main

import "fmt"
import "os"

func defaults() map {
  m := make(map[string]string)
  m["start"] = "1"
  m["from"]  = "encrypted"
  m["to"]    = "loaded"
  return m
}

func main() {
  args := os.Args[1:]
  fmt.Println(args)
  runvals := defaults()
  fmt.Println(runvals)
}

Errors I'm getting:

Line 6 col 21 error| expected '[', found '{'
Line 7 col 5 error| expected ']', found ':='
Line 11 col 3 error| expected declaration, found 'return'

Can someone help me get the syntax right? Or am I trying to do something that Go doesn't do?

func defaults() map[string] string {
    m := make(map[string]string)
    m["start"] = "1"
    ...
    return m
}

The problem with your defaults function is the return type map has no types.

You need to declare the whole type including key and value types.

func defaults() map[string]string {
    …
}