Make IO functions nicer

01/main.go

 }
 
 func main() {
-	input := common.Atoi(common.ReadLines("01/input.txt"))
+	input := common.ReadFileAsInts("01/input.txt")
 	part1, part2 := fuelRequirements(input)
 	fmt.Println(part1)
 	fmt.Println(part2)

02/main.go

 }
 
 func main() {
-	input := common.Atoi(common.ReadCommas("02/input.txt"))
+	input := common.ReadCsvAsInts("02/input.txt")
 
 	pool := &sync.Pool{
 		New: func() interface{} {

common/io.go

 	"unicode/utf8"
 )
 
-// ReadLines reads all lines from the given path and returns them in a slice of strings.
+// ReadFileAsInts reads all lines from the given path and returns them in a slice of ints.
 // If an error occurs, the function will panic.
-func ReadLines(path string) []string {
-	return readWithScanner(path, bufio.ScanLines)
+func ReadFileAsInts(path string) []int {
+	return readIntsWithScanner(path, bufio.ScanLines)
 }
 
-// ReadCommas reads all data from the given path and returns a string slice
-// containing comma-delimited parts. If a
-// If an error occurs, the function will panic.
-func ReadCommas(path string) []string {
-	return readWithScanner(path, scanByCommas)
+// ReadCsvAsInts reads all data from the given path and returns an int slice
+// containing comma-delimited parts.  If an error occurs, the function will panic.
+func ReadCsvAsInts(path string) []int {
+	return readIntsWithScanner(path, scanByCommas)
 }
 
-func readWithScanner(path string, splitFunc bufio.SplitFunc) []string {
+func readIntsWithScanner(path string, splitFunc bufio.SplitFunc) []int {
 	file, err := os.Open(path)
 	if err != nil {
 		panic(err)
 		_ = file.Close()
 	}()
 
-	var parts []string
+	var parts []int
 	scanner := bufio.NewScanner(file)
 	scanner.Split(splitFunc)
 	for scanner.Scan() {
-		parts = append(parts, scanner.Text())
+		parts = append(parts, MustAtoi(scanner.Text()))
 	}
 
 	if scanner.Err() != nil {

common/strings.go

 	}
 	return res
 }
-
-// Atoi converts a slice of strings to a slice of integers.
-// It panics if any element couldn't be converted.
-func Atoi(input []string) []int {
-	var result []int
-	for _, element := range input {
-		result = append(result, MustAtoi(element))
-	}
-	return result
-}