comments

go/03-modules/main.go

@@ -3,9 +3,17 @@ package main
 import (
 	"fmt"
 
+	// importing the myMath package with an alias mm. This allows us to use mm instead of myMath to access the functions in the package.
+	// go packages are imported using their full path, which is the path to the package relative to the GOPATH or module root. .
 	mm "gitty.informatik.hs-mannheim.de/steger/pr3-code/go/03-modules/myMath"
-	//_ "gitty.informatik.hs-mannheim.de/steger/pr3-code/go/03-modules/myMath"
 
+	// the underscore is used to import a package solely for its side effects (i.e., the init function).
+	// This is useful when you want to initialize a package but do not need to access any of its exported functions or variables.
+	// _ "gitty.informatik.hs-mannheim.de/steger/pr3-code/go/03-modules/myMath"
+
+	// importing a third-party package from GitHub. This package provides functions for generating UUIDs (Universally Unique Identifiers).
+	// To use this package, you need to run go get github.com/google/uuid to download and install the package in your Go workspace.
+	// Alternatively, you can run go mod tidy to automatically download and install any missing dependencies based on the imports in your code.
 	"github.com/google/uuid"
 	//run go get github.com/google/uuid
 	//or go mod tidy => go.sum

go/03-modules/myMath/math.go

@@ -2,14 +2,18 @@ package myMath
 
 import "fmt"
 
+// init is a special function that is called automatically when the package is imported. It is used to initialize the package
+// and can be used to set up any necessary state or perform any necessary setup before the package is used.
 func init() {
 	fmt.Println("initializing myMath")
 }
 
+// functions that start with an uppercase letter are exported and can be accessed from outside the package
 func Add(a, b int) int {
 	return a + b
 }
 
+// functions that start with a lowercase letter are not exported and cannot be accessed from outside the package
 func greater(a, b int) bool {
 	return a > b
 }