A Tour of Go Maps

A map maps keys to values.

Maps must be created with

make

(not

new

) before use; the

nil

map is empty and cannot be assigned to.

package main

import "fmt"

type Vertex struct{
Lat, Long float64
}

var m map[string]Vertex

func main() {
m = make(map[string]Vertex)
m["Bell Labs"] = Vertex{
40.68433, -74.39967,
}
fmt.Println(m["Bell Labs"])
}