Merge pull request #22 from hegdeashwin/develop

Develop

Author: Ashwin Hegde

codes/ch5_maps/check-existence-into-map.go

@@ -0,0 +1,38 @@
+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 {
+		delete(prefixMap, "Saju")
+	}
+
+	/**
+	 * Check if the value exist into the map or not.
+	 */
+	if _, exists := prefixMap[name]; exists {
+		return prefixMap[name]
+	} else {
+		return "dude"
+	}
+
+}
+
+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/ch6_slices/appending-to-slices.go

@@ -0,0 +1,35 @@
+package main
+
+import "fmt"
+
+func main() {
+
+	/**
+	 * Blank [] will declare a slices.
+	 * If you provide size like [5] will declare an array.
+	 */
+	var employee []string
+
+	/**
+	 * Initialize a slices with type, length and capacity.
+	 * length is required field.
+	 * 
+	 * make([]string, length, [capacity])
+	 */
+	employee = make([]string, 3)
+
+	employee[0] = "Ashwin"
+	employee[1] = "Kumar"
+	employee[2] = "Saju"
+
+	fmt.Println("Slices: ", employee)
+
+	/**
+	 * Appending into slices.
+	 */
+	employee = append(employee, "Ajay")
+	employee = append(employee, "Vinayak")
+
+	fmt.Println("After appending: ", employee)
+
+}

codes/ch6_slices/create-a-slices.go

@@ -0,0 +1,23 @@
+package main
+
+func main() {
+
+	/**
+	 * Blank [] will declare a slices.
+	 * If you provide size like [5] will declare an array.
+	 */
+	var employee []string
+
+	/**
+	 * Initialize a slices with type, length and capacity.
+	 * length is required field.
+	 * 
+	 * make([]string, length, [capacity])
+	 */
+	employee = make([]string, 3)
+
+	employee[0] = "Ashwin"
+	employee[1] = "Kumar"
+	employee[2] = "Saju"
+	// employee[3] = "Ajay" // This will throw an error `out of range`
+}

codes/ch6_slices/delete-from-a-slices.go

@@ -0,0 +1,36 @@
+package main
+
+import "fmt"
+
+func main() {
+
+	/**
+	 * Blank [] will declare a slices.
+	 * If you provide size like [5] will declare an array.
+	 */
+	var employee []string
+
+	/**
+	 * Initialize a slices with type, length and capacity.
+	 * length is required field.
+	 * 
+	 * make([]string, length, [capacity])
+	 */
+	employee = make([]string, 6)
+
+	employee[0] = "Ashwin"
+	employee[1] = "Kumar"
+	employee[2] = "Saju"
+	employee[3] = "Ajay"
+	employee[4] = "Vinayak"
+	employee[5] = "Jerin"
+
+	fmt.Println("Slices: ", employee)
+
+	// 0:2 - include 0, 1 but excludes 2
+	// 4:  - include last
+	// ... - expanding slices
+	employee = append(employee[0:2], employee[4:]...)
+
+	fmt.Println("After Delete: ", employee)
+}

codes/ch6_slices/short-hand-way.go

@@ -0,0 +1,12 @@
+package main
+
+func main() {
+
+	/**
+	 * Short hand way to declare and initialize slices
+	 */
+	employee := []string {
+		"Ashwin", "Kumar", "Saju", "Ajay"
+	}
+
+}

codes/ch6_slices/slicing-slices.go

@@ -0,0 +1,49 @@
+package main
+
+import "fmt"
+
+func main() {
+
+	/**
+	 * Blank [] will declare a slices.
+	 * If you provide size like [5] will declare an array.
+	 */
+	var employee []string
+
+	/**
+	 * Initialize a slices with type, length and capacity.
+	 * length is required field.
+	 * 
+	 * make([]string, length, [capacity])
+	 */
+	employee = make([]string, 7)
+
+	employee[0] = "Ashwin"
+	employee[1] = "Kumar"
+	employee[2] = "Saju"
+	employee[3] = "Ajay"
+	employee[4] = "Jerin"
+	employee[5] = "Vinayak"
+	employee[6] = "Pavan"
+
+	/**
+	 * Slices and updating slices
+	 */
+	employee = employee[0:]
+	fmt.Println("[0:]", employee)
+
+	employee = employee[0:7]
+	fmt.Println("[0:7]", employee)
+
+	employee = employee[0:len(employee)]
+	fmt.Println("[0:len(employee)]", employee)
+
+	employee = employee[:4]
+	fmt.Println("[0:4]", employee)
+
+	employee = employee[0:4]
+	fmt.Println("[:4]", employee)
+
+	employee = employee[4:7]
+	fmt.Println("[4:7]", employee)
+}