Merge pull request #21 from hegdeashwin/develop

Develop

Author: Ashwin Hegde

codes/ch5_maps/create-a-map.go

@@ -0,0 +1,21 @@
+package main
+
+/**
+ * Note: The code will not run and throw an error: prefixMap declared and not used
+ * As we have declare map and not used in and this is error in go-lang
+ */
+func main() {
+
+	/**
+	 * Declare a map of map type with string.
+	 * var <variable-name> map[<key-type>] <value-type>
+	 */
+	var prefixMap map[string] string
+
+	/**
+	 * make will initialize the map; if we don't use make 
+	 * declaration will set to null;
+	 */
+	prefixMap = make(map[string] string)
+
+}

codes/ch5_maps/delete-into-a-map.go

@@ -0,0 +1,39 @@
+package main
+
+import "fmt";
+
+func GetPrefix(name string, mustDel bool) (prefix string) {
+
+	/**
+	 * Short hand way to declare and initialize map
+	 */
+	prefixMap := map[string] string {
+		"Ashwin": "Sr. Fullstack Engineer",
+		"Kumar": "Sr. Engineering Manager",
+		"Saju": "Sr. Solution Architect",
+		"Ajay": "Sr. Solution Architect", // comma is needed here
+	}
+
+	if mustDel {
+		/**
+		 * Old way to perform delete operation on map.
+		 * Will no more work for new version of Go compiler
+		 */
+		// prefixMap["Saju"] = "", false
+
+		/**
+		 * New way to perform delete operation on map.
+		 */
+		delete(prefixMap, "Saju")
+	}
+	
+	return prefixMap[name]
+}
+
+func main() {
+
+	fmt.Println("What is Saju's role? He is " + GetPrefix("Saju", false))
+
+	fmt.Println("What is Saju's role? He is " + GetPrefix("Saju", true))
+
+}

codes/ch5_maps/insert-into-a-map.go

@@ -0,0 +1,27 @@
+package main
+
+import "fmt";
+
+func GetPrefix(name string) (prefix string) {
+
+	var prefixMap map[string] string
+	prefixMap = make(map[string] string)
+
+	/**
+	 * Insert key and value into the map.
+	 *
+	 * <map-variable>[<key>] = <value>
+	 */
+	prefixMap["Ashwin"] = "Sr. Fullstack Engineer"
+	prefixMap["Kumar"] = "Sr. Engineering Manager"
+	prefixMap["Saju"] = "Sr. Solution Architect"
+	prefixMap["Ajay"] = "Sr. solution Architect"
+
+	return prefixMap[name]
+}
+
+func main() {
+
+	fmt.Println("What is Ashwin's role? He is " + GetPrefix("Ashwin"))
+
+}

codes/ch5_maps/short-hand-way.go

@@ -0,0 +1,24 @@
+package main
+
+import "fmt";
+
+func GetPrefix(name string) (prefix string) {
+
+	/**
+	 * Short hand way to declare and initialize map
+	 */
+	prefixMap := map[string] string {
+		"Ashwin": "Sr. Fullstack Engineer",
+		"Kumar": "Sr. Engineering Manager",
+		"Saju": "Sr. Solution Architect",
+		"Ajay": "Sr. Solution Architect", // comma is needed here
+	}
+
+	return prefixMap[name]
+}
+
+func main() {
+
+	fmt.Println("What is Ashwin's role? He is " + GetPrefix("Ashwin"))
+
+}

codes/ch5_maps/update-into-a-map.go

@@ -0,0 +1,31 @@
+package main
+
+import "fmt";
+
+func GetPrefix(name string) (prefix string) {
+
+	/**
+	 * Short hand way to declare and initialize map
+	 */
+	prefixMap := map[string] string {
+		"Ashwin": "Sr. Fullstack Engineer",
+		"Kumar": "Sr. Engineering Manager",
+		"Saju": "Sr. Solution Architect",
+		"Ajay": "Sr. Solution Architect", // comma is needed here
+	}
+
+	/**
+	 * Perform update operation on map.
+	 */
+	prefixMap["Kumar"] = "Delivery Manager"
+	prefixMap["Ajay"] = "Sr. Project Manager"
+
+	return prefixMap[name]
+}
+
+func main() {
+
+	fmt.Println("What is Kumar's role? He is " + GetPrefix("Kumar"))
+	fmt.Println("What is Ajay's role? He is " + GetPrefix("Ajay"))
+
+}