Iterating over all the keys of a map

https://play.golang.org/p/JGZ7mN0-U-

for k, v := range m { 
    fmt.Printf("key[%s] value[%s]\n", k, v)
}

or

for k := range m {
    fmt.Printf("key[%s] value[%s]\n", k, m[k])
}

Go language specs for for statements specifies that the first value is the key, the second variable is the value, but doesn't have to be present.

Here's some easy way to get slice of the map-keys.

// Return keys of the given map
func Keys(m map[string]interface{}) (keys []string) {
    for k := range m {
        keys = append(keys, k)
    }
    return keys
}

// use `Keys` func
func main() {
    m := map[string]interface{}{
        "foo": 1,
        "bar": true,
        "baz": "baz",
    }
    fmt.Println(Keys(m)) // [foo bar baz]
}

Is there a way to get a list of all the keys in a Go language map?

ks := reflect.ValueOf(m).MapKeys()

how do I iterate over all the keys?

Use the accepted answer:

for k, _ := range m { ... }