cmd/headFirstCodeMagnets/variadic.go

@@ -3,7 +3,7 @@ package main
 import "fmt"
 
 func sum(numbers ...int) int {
-	var sum = 0
+	var sum int = 0
 
 	for _, number := range numbers {
 		sum += number

cmd/playground/averageHeadFirstVariadic.go

@@ -14,7 +14,7 @@ func averageCalc(numbers ...float64) float64 {
 	return sum / float64(len(numbers))
 }
 
-func main() {
+func averageHeadFirstVariadic() {
 	arguments := os.Args[1:]
 	var numbers []float64
 	for _, argument := range arguments {
@@ -22,5 +22,5 @@ func main() {
 		Error(err)
 		numbers = append(numbers, number)
 	}
-	fmt.Printf("Average: %0.2f\n", averageCalc(numbers...))
+	fmt.Printf("Average: %0.2\n", averageCalc(numbers...))
 }

cmd/playground/variadic.go

@@ -6,13 +6,13 @@ import (
 )
 
 func maximum(numbers ...float64) float64 {
-	maxNumber := math.Inf(-1)
+	max := math.Inf(-1)
 	for _, number := range numbers {
-		if number > maxNumber {
+		if number > max {
-			maxNumber = number
+			max = number
 		}
 	}
-	return maxNumber
+	return max
 }
 
 func inRange(min float64, max float64, numbers ...float64) []float64 {

cmd/playground/wallArea.go

@@ -5,10 +5,10 @@ import "fmt"
 func paintNeeded(width float64, height float64) (paintNeededCalculated float64, anError error) {
 	area := width * height
 	if width < 0.0 {
-		return 0, fmt.Errorf("a width of %0.2f is invalid", width)
+		return 0, fmt.Errorf("a width of %0.2f is invalid.", width)
 	}
 	if height < 0.0 {
-		return 0, fmt.Errorf("a height of %0.2f is invalid", height)
+		return 0, fmt.Errorf("a height of %0.2f is invalid.", height)
 	}
 	return area / 10.0, nil
 }

cmd/sum/sum.go

@@ -15,10 +15,7 @@ func OpenFile(fileName string) (*os.File, error) {
 
 func CloseFile(file *os.File) {
 	fmt.Println("Closing file")
-	err := file.Close()
+	file.Close()
-	if err != nil {
-		log.Fatal(err)
-	}
 }
 
 func GetFloats(fileName string) ([]float64, error) {