Add code

1-pointers-in-go/Makefile

@@ -0,0 +1,2 @@
+all:
+	go run main.go

1-pointers-in-go/main.go

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+package main
+
+import (
+    "fmt"
+    "time"
+)
+
+type Person struct {
+    firstName string
+    lastName string
+    birthday time.Time
+}
+
+func main() {
+    birthday, _ := time.Parse("2006-Jan-02", "1994-Aug-10")
+
+    person := Person{
+        firstName: "Alex",
+        lastName: "Kotov",
+        birthday: birthday,
+    }
+
+    printPersonByValue(person)
+    printPersonByRefSafe(&person)
+    printPersonByRefUnsafe(&person)
+    printPersonByRefSafe(nil)
+    printPersonByRefUnsafe(nil)
+}
+
+func printPersonByValue(person Person) {
+    fmt.Println("=== by value =====================================")
+    fmt.Println("First name:", person.firstName)
+    fmt.Println("Last name: ", person.lastName)
+    fmt.Println("Birthday:  ", person.birthday)
+}
+
+func printPersonByRefSafe(person *Person) {
+    fmt.Println("=== by reference (safe) ==========================")
+
+    if person == nil {
+        fmt.Println("nil pointer, skip...")
+        return
+    }
+
+    fmt.Println("First name:", person.firstName)
+    fmt.Println("Last name: ", person.lastName)
+    fmt.Println("Birthday:  ", person.birthday)
+}
+
+func printPersonByRefUnsafe(person *Person) {
+    fmt.Println("=== by reference (unsafe) ========================")
+    fmt.Println("First name:", person.firstName)
+    fmt.Println("Last name: ", person.lastName)
+    fmt.Println("Birthday:  ", person.birthday)
+}