complete the tasks: type conversion

Author: nvp85

explicit-and-implicit-conversion-in-javascript.js

@@ -18,15 +18,30 @@ Use console.log() to clearly show the before-and-after type conversions.
 
 */
 
-
-let result = "5" - 2;
+// JavaScript converts "5" into a number so the result is correct. But better to convert it explicitely for clarity:
+let result = Number("5") - 2;
 console.log("The result is: " + result);
 
-let isValid = Boolean("false");
-if (isValid) {
+let isValid = "false"; // Boolean() converts the string "false" into true because it is not empty
+// fix: remove Boolean(), compare to the string "true" instead
+if (isValid === "true") {
     console.log("This is valid!");
 }
 
 let age = "25";
-let totalAge = age + 5;
+let totalAge = Number(age) + 5; // JavaScript converts 5 into a string and concatinates two strings. 
+// Fix: use Number() to convert age into a number.
 console.log("Total Age: " + totalAge);
+
+//  - One example of implicit type conversion.
+let implicitStrToNum = "2" * 2; // string "2" is converted into a number 
+console.log(implicitStrToNum); // Output: 4
+
+console.log("Hi" * 5); // Output: NaN. "Hi" cannot be converted into a number
+console.log(null + 5); // Output: 5. Null is converted into 0
+
+//  - One example of explicit type conversion.
+let explicitNullToBool = Boolean(null);
+console.log(explicitNullToBool); // Output: false
+// explicit null to string:
+console.log(String(null) + "Hi"); // Output: "nullHi". null is converted into a string "null"