maps.go

package main

import (
	"fmt"
)

// Maps function to detail the map built-in associative data type
func Maps() {

	// To create an empty map, use the builtin make: make(map[key-type]val-type).
	m := make(map[string]int)

	// Set key/value pairs using typical name[key] = val syntax.
	m["k1"] = 7
	m["k2"] = 13

	// Printing a map with e.g. fmt.Println will show all of its key/value pairs.
	fmt.Println("map:", m)

	// Get a value for a key with name[key].
	v1 := m["k1"]
	fmt.Println("v1: ", v1)

	// The builtin len returns the number of key/value pairs when called on a map.
	fmt.Println("len: ", len(m))

	// The builtin delete removes key/value pairs from a map.
	delete(m, "k2")
	fmt.Println("map: ", m)

	// The optional second return value when getting a value from a map indicates if the key was present in the map.
	// This can be used to disambiguate between missing keys and keys with zero values like 0 or "".
	// Here we didn’t need the value itself, so we ignored it with the blank identifier _.
	_, prs := m["k2"]
	fmt.Println("prs: ", prs)

	// You can also declare and initialize a new map in the same line with this syntax.
	n := map[string]int{
		"foo": 1,
		"bar": 2,
	}
	fmt.Println("map: ", n)

	// Note that maps appear in the form map[k:v k:v] when printed with fmt.Println.
}