bugfix CLI parsing

cmd/hashcash/hashcash.go

@@ -12,7 +12,7 @@ import (
 
 func help() {
 	fmt.Println("Usage:")
-	fmt.Println("\thashcash new [subject *] [expires in 5m] [difficulty 10]")
+	fmt.Println("\thashcash new [subject *] [difficulty 10] [expires in 5m]")
 	fmt.Println("\thashcash parse <hashcash>")
 	fmt.Println("\thashcash solve <hashcash>")
 	fmt.Println("\thashcash verify <hashcash> [subject *]")
@@ -20,8 +20,9 @@ func help() {
 
 func main() {
 	args := os.Args[:]
+	nargs := len(args)
 
-	if len(args) < 2 {
+	if nargs < 2 {
 		help()
 		os.Exit(1)
 		return
@@ -30,27 +31,30 @@ func main() {
 	switch args[1] {
 	case "new":
 		var subject string
-		if len(args) > 3 {
+		if nargs >= 3 {
 			subject = args[2]
 		}
 
 		var difficulty int
-		if len(args) > 4 {
+		if nargs >= 4 {
 			var err error
 			difficulty, err = strconv.Atoi(args[3])
 			if nil != err {
 				help()
 				os.Exit(1)
+				return
 			}
 		}
 
 		var expIn time.Duration
-		if len(args) > 5 {
+		if nargs >= 5 {
 			var err error
 			expIn, err = time.ParseDuration(args[4])
 			if nil != err {
+				fmt.Println(err)
 				help()
 				os.Exit(1)
+				return
 			}
 		} else {
 			expIn = 5 * time.Minute
@@ -66,7 +70,7 @@ func main() {
 		return
 	case "parse":
 		var token string
-		if 3 != len(args) {
+		if 3 != nargs {
 			help()
 			os.Exit(1)
 			return
@@ -82,7 +86,7 @@ func main() {
 		return
 	case "solve":
 		var token string
-		if 3 != len(args) {
+		if 3 != nargs {
 			help()
 			os.Exit(1)
 			return
@@ -105,7 +109,7 @@ func main() {
 		return
 	case "verify":
 		var token string
-		if len(args) < 3 {
+		if nargs < 3 {
 			help()
 			os.Exit(1)
 			return
@@ -118,7 +122,7 @@ func main() {
 		}
 
 		subject := "*"
-		if len(args) > 3 {
+		if nargs >= 4 {
 			subject = args[3]
 		}