Collections and Composite Types

Maps

Maps store values by key, which makes lookup code direct.

Maps

maps_intro.go 
package main

import "fmt"

func main() {
	var key = 
	scores := map[string]int{
		"go":     95,
		"ruby":   88,
		"python": 92,
	}
	value := scores[key]

	fmt.Println("key=", key)
	fmt.Println("value=", value)
}

package main

import "fmt"

func main() {
	var key = 
	scores := map[string]int{
		"go":     95,
		"ruby":   88,
		"python": 92,
	}
	value := scores[key]

	fmt.Println("key=", key)
	fmt.Println("value=", value)
}

package main

import "fmt"

func main() {
	var key = 
	scores := map[string]int{
		"go":     95,
		"ruby":   88,
		"python": 92,
	}
	value := scores[key]

	fmt.Println("key=", key)
	fmt.Println("value=", value)
}
map lookup A map lookup such as `scores[key]` returns the value stored for that key.