Section6.54

Section6/52.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+)
+
+func main() {
+	/* 	fmt.Println("os.Args", os.Args)
+	   	fmt.Println("Path:", os.Args[0])
+	   	fmt.Println("1st argument:", os.Args[1])
+	   	fmt.Println("2nd argument:", os.Args[2])
+	   	fmt.Println("No if items inside os.Args:", len(os.Args)) */
+
+	var results, err = strconv.ParseFloat(os.Args[1], 64)
+	fmt.Println(results)
+	fmt.Printf("%T\n", os.Args[1])
+	fmt.Printf("%T\n", results)
+	_ = err
+}

Section6/54.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+)
+
+func main() {
+	i, err := strconv.Atoi("45")
+
+	if err != nil {
+		fmt.Println(err)
+	} else {
+		fmt.Println(i)
+	}
+
+	if i, err := strconv.Atoi("20X"); err == nil { //20X can not be converted to int
+		fmt.Println("No error, i is:", i)
+	} else {
+		fmt.Println(err)
+	}
+
+	if args := os.Args; len(args) != 2 {
+		fmt.Println("One argument is required")
+	} else if km, err := strconv.Atoi(args[1]); err != nil {
+		fmt.Println("The argument must be an integer! Error:", err)
+	} else {
+		fmt.Printf("%d km in miles is %v\n", km, float64(km)*0.621)
+		fmt.Printf("%T\n", args[1])
+	}
+
+}