Go Structs and Code cleanup

Author: Rajeev Kumar Singh

09-pointers/04-pointer-new-function/main.go

@@ -0,0 +1,11 @@
+package main
+
+import "fmt"
+
+func main() {
+	// You can create a pointer using the built-in new() function
+	ptr := new(int) // Pointer to an int
+	*ptr = 100
+
+	fmt.Printf("Ptr = %#x, Ptr value = %d\n", ptr, *ptr)
+}

09-pointers/04-pointer-to-pointer/main.go renamed to 09-pointers/05-pointer-to-pointer/main.go

@@ -12,21 +12,23 @@ type Person struct {
 }
 
 func main() {
-	// Creating an instance of the 'person' struct type
+	// Declaring a variable of a `struct` type
+	var p Person // // All the struct fields are initialized with their zero value
+	fmt.Println(p)
+
+	// Declaring and initializing a struct using a struct literal
 	p1 := Person{"Rajeev", "Singh", 26}
 	fmt.Println("Person1: ", p1)
 
-	// Naming fields while initializing the struct
+	// Naming fields while initializing a struct
 	p2 := Person{
 		firstName: "John",
 		lastName:  "Snow",
 		age:       45,
 	}
 	fmt.Println("Person2: ", p2)
 
-	// Uninitialized fields are assigned their zero-value
-	p3 := Person{
-		firstName: "Robert",
-	}
+	// Uninitialized fields are set to their corresponding zero-value
+	p3 := Person{firstName: "Robert"}
 	fmt.Println("Person3: ", p3)
 }

09-pointers/05-pointer-arithmetic/main.go renamed to 09-pointers/06-pointer-arithmetic/main.go

@@ -17,7 +17,7 @@ func main() {
 		weightInKg: 1920,
 	}
 
-	// Accessing struct fields using dot notation
+	// Accessing struct fields using the dot operator
 	fmt.Println("Car name: ", c.name)
 	fmt.Println("Car color: ", c.color)
 

09-pointers/06-pointer-equality/main.go renamed to 09-pointers/07-pointer-equality/main.go

@@ -13,7 +13,7 @@ func main() {
 	// instance of student struct type
 	s := Student{11, "Jack"}
 
-	// Pointer to a student struct
+	// Pointer to the student struct
 	ps := &s
 	fmt.Println(ps)
 

10-structs/01-struct-declaration-initialization/main.go

@@ -0,0 +1,19 @@
+package main
+
+import "fmt"
+
+type Employee struct {
+	id   int
+	name string
+}
+
+func main() {
+	// You can also get a pointer to a struct using the built-in new() function
+	// It allocates enough memory to fit a value of the given struct type, and returns a pointer to it
+	pEmp := new(Employee)
+
+	pEmp.id = 1000
+	pEmp.name = "Sachin"
+
+	fmt.Println(pEmp)
+}

10-structs/02-struct-access-fields/main.go

@@ -16,14 +16,17 @@ type Customer struct {
 }
 
 func main() {
-	c := Customer{name: "Rajeev Singh", age: 25}
-	c.address = Address{
-		houseNo: "747",
-		street:  "Golf View Road",
-		city:    "Seattle",
-		state:   "Washington",
-		country: "United States",
-		zipCode: 98101,
+	c := Customer{
+		name: "Rajeev Singh",
+		age:  25,
+		address: Address{
+			houseNo: "747",
+			street:  "Golf View Road",
+			city:    "Seattle",
+			state:   "Washington",
+			country: "United States",
+			zipCode: 98101,
+		},
 	}
 
 	fmt.Println("Customer: ", c)