maps in go code example

Example 1: initialize map in golang

// By default maps in Go behaves like a default dictionary in python
m := make(map[string]int)

m["Dio"] = 3
m["Jonathan"] = 1

Example 2: go remove from map

m := map[string]string{"key1": "val1", "key2": "val2"}
delete(m, "key1")

Example 3: go maps

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"])
}

Example 4: go maps

var m map[string]int
m = make(map[string]int)
m["key"] = 42
fmt.Println(m["key"])

delete(m, "key")

elem, ok := m["key"] // test if key "key" is present and retrieve it, if so

// map literal
var m = map[string]Vertex{
    "Bell Labs": {40.68433, -74.39967},
    "Google":    {37.42202, -122.08408},
}

// iterate over map content
for key, value := range m {
}