map.go

package main

import "fmt"

func main() {
	// map is a collection of key-value pairs
	// create a map with make function
	person := make(map[string]string)

	// add key-value pairs to the map
	person["name"] = "Muhammad Luthfi"
	person["address"] = "Jakarta"
	person["occupation"] = "Software Engineer"

	println("Name:", person["name"])
	println("Address:", person["address"])
	println("Occupation:", person["occupation"])
	fmt.Println(person) // fo display more details use fmt.Println

	fmt.Println("---------------------------------------------------")
	// create a new map with map literal
	books := map[string]string{
		"title":  "The Go Programming Language",
		"author": "Alan A. A. Donovan",
		"year":   "2015",
	}

	println("Book Title:", books["title"])
	println("Book Author:", books["author"])
	println("Publication Year:", books["year"])
	fmt.Println(books)

	// built-in function
	// len() to get the number of key-value pairs in the map
	fmt.Println("Number of books info:", len(books))

	// delete key-value pair from the map
	delete(books, "year")
	fmt.Println(books)

	// change map value
	books["author"] = "Brian W. Kernighan"
	fmt.Println(books)

	// add map value
	books["publisher"] = "Addison-Wesley"
	fmt.Println(books)
}