If the top-level type is just a type name, you can omit it from the elements of the literal.

package main import "fmt"type Vertex struct {    Lat, Long float64}var m = map[string]Vertex {    "Bell Labs": {
   40.68433,-74.39967},    "Google": {
   37.42202, -122.08408},}func main() {    var m2 map[int]uint8    m2 = make(map[int]uint8)    m2[12] = uint8(12)    m2[1] = uint8(1)    fmt.Println(m)    fmt.Println(m2)}