Added maps tutorial under go_basics

Author: anarchymonkey

go_basics/go.work

@@ -6,6 +6,7 @@ use (
 	./datatypes
 	./defer_panic_recover
 	./functions
+	./gomaps
 	./loops
 	./numeric_constants
 	./pointers

go_basics/gomaps/go.mod

@@ -0,0 +1,3 @@
+module anarchymonkey.com/go-basics/gomaps
+
+go 1.20

go_basics/gomaps/gomaps.go

@@ -0,0 +1,124 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"unicode/utf8"
+)
+
+type Address struct {
+	city            string
+	state           string
+	basicAddress    string
+	extendedAddress string
+	pincode         int
+}
+type UserProfile struct {
+	name     string
+	nickName string
+
+	age int
+
+	address Address
+}
+
+func WordCount(s string) (map[string]int, error) {
+
+	if !utf8.ValidString(s) || s == "" {
+		return nil, errors.New("Cannot parse non utf-8 embedded string")
+	}
+	wordCount := make(map[string]int)
+
+	for _, value := range strings.Split(s, " ") {
+		if _, hasKey := wordCount[string(value)]; hasKey {
+			wordCount[string(value)] = wordCount[string(value)] + 1
+		} else {
+			wordCount[string(value)] = 1
+		}
+	}
+
+	return wordCount, nil
+}
+
+var m map[string]UserProfile
+
+func GetUserProfile() {
+	// What are maps?
+	// Ans: Maps are just a store of keys and values
+
+	m = make(map[string]UserProfile)
+
+	m["Aniket"] = UserProfile{
+		name:     "Aniket",
+		nickName: "Rick",
+		age:      27,
+		address: Address{
+			city:            "Bangalore",
+			state:           "Karnataka",
+			basicAddress:    "Jhingalala huhu",
+			extendedAddress: "huhu huhu",
+			pincode:         560001,
+		},
+	}
+
+	fmt.Println("Maps")
+	fmt.Println("Map: ", m["Aniket"])
+
+	// map literals
+
+	var mapLiteral map[string]UserProfile = map[string]UserProfile{
+		"Meeta": {
+			name:     "Meeta",
+			nickName: "Meetu",
+			age:      27,
+			address: Address{
+				city:            "Bangalore",
+				state:           "Karnataka",
+				basicAddress:    "Jhingalala huhu",
+				extendedAddress: "huhu huhu",
+				pincode:         560075,
+			},
+		},
+		"Aniket": {
+			name:     "Aniket",
+			nickName: "Rick",
+			age:      26,
+			address: Address{
+				city:            "Bangalore",
+				state:           "Karnataka",
+				basicAddress:    "Jhingalala huhu",
+				extendedAddress: "huhu huhu",
+				pincode:         560015,
+			},
+		},
+	}
+
+	for key, userProfile := range mapLiteral {
+		fmt.Printf("Nickname at index = %s is %v \n", key, userProfile.address)
+	}
+
+	aniketsDetails := mapLiteral["Aniket"]
+
+	fmt.Println("Anikets details are ", aniketsDetails)
+
+	// delete a key
+
+	delete(mapLiteral, "Meeta")
+
+	// check if key exists or not
+
+	elem, ok := mapLiteral["Aniket"]
+
+	if ok {
+		fmt.Println("The values are", elem, ok)
+	}
+}
+
+func main() {
+	GetUserProfile()
+
+	fmt.Println("Word count map is ")
+	fmt.Println(WordCount("Hey my name is Aniket"))
+	fmt.Println(WordCount("Aniket is awesome, Aniket is so good"))
+}

go_basics/gomaps/gomaps_test.go

@@ -0,0 +1,42 @@
+package main
+
+import "testing"
+
+func TestWordCount(t *testing.T) {
+
+	actual_output, error := WordCount("Hey my name is Aniket")
+
+	if error != nil {
+		t.Error("Found error", error)
+		return
+	}
+
+	newMap := make(map[string]int)
+
+	newMap = map[string]int{
+		"Aniket": 1,
+		"is":     1,
+		"name":   1,
+		"my":     1,
+		"Hey":    1,
+	}
+
+	for key, value := range actual_output {
+		keyCountInNewMap := newMap[key]
+		actualOutputCount := value
+
+		if actualOutputCount != keyCountInNewMap {
+			t.Error("The map count does not match")
+		}
+	}
+}
+
+func TestWordCountEmpty(t *testing.T) {
+
+	_, error := WordCount("")
+
+	if error == nil {
+		t.Error("Found error", error)
+		return
+	}
+}