Organized code and improved error handling

Added really primitive error handling to numStar scanning, I really have
to figure out how to properly handle errors in Golang beyond abusing
if/else and switch/case

star-shapes/go.mod

@@ -0,0 +1,3 @@
+module star-shapes
+
+go 1.21.6

star-shapes/main.go

@@ -11,11 +11,28 @@ func main() {
 	var numShape int
 
 	// TODO: Add error handling for star number
-	fmt.Println("How many stars do you want?")
-	fmt.Printf("    Stars: ")
-	fmt.Scan(&numStar)
+forStars:
+	for {
 
-	fmt.Printf("\n")
+		fmt.Println("How many stars do you want?")
+		fmt.Printf("    Stars: ")
+		fmt.Scan(&numStar)
+
+		// This is confusing
+		// switch v := interface{}(numStar).(type) {
+		// case int:
+		// 	break forStars
+		// default:
+		// 	fmt.Printf("ERROR, %v is invalid input", v)
+		// 	panic("ERROR")
+		// }
+
+		if numStar >= 0 {
+			break forStars
+		} else {
+			fmt.Printf("\n[-] INVALID NUMBER\n\n")
+		}
+	}
 
 forShapes:
 	for {
@@ -38,31 +55,3 @@ forShapes:
 		}
 	}
 }
-
-func line(num int) {
-	for i := 0; i < num; i++ {
-		fmt.Printf("* ")
-	}
-	fmt.Printf("\n")
-}
-
-func square(num int) {
-	for i := 0; i < num; i++ {
-		for i := 0; i < num; i++ {
-			fmt.Printf("* ")
-		}
-		fmt.Printf("\n")
-	}
-}
-
-func flag(num int) {
-	for a := 0; a < num; a++ {
-		for i := -1; i < a; i++ {
-			fmt.Printf("* ")
-		}
-		fmt.Printf("\n")
-	}
-	for i := 0; i < num/2; i++ {
-		println("*")
-	}
-}

star-shapes/shapes.go

@@ -0,0 +1,34 @@
+package main
+
+import "fmt"
+
+// Drawing a line of asterisks
+func line(num int) {
+	for i := 0; i < num; i++ {
+		fmt.Printf("* ")
+	}
+	fmt.Printf("\n")
+}
+
+// Drawing a square of asterisks
+func square(num int) {
+	for i := 0; i < num; i++ {
+		for i := 0; i < num; i++ {
+			fmt.Printf("* ")
+		}
+		fmt.Printf("\n")
+	}
+}
+
+// Drawing a flag of asterisks
+func flag(num int) {
+	for a := 0; a < num; a++ {
+		for i := -1; i < a; i++ {
+			fmt.Printf("* ")
+		}
+		fmt.Printf("\n")
+	}
+	for i := 0; i < num/2; i++ {
+		println("*")
+	}
+}