2-mandatory-errors completed

Author: bartoszkawiak

Sprint-2/2-mandatory-errors/0.js

@@ -1,2 +1,5 @@
 This is just an instruction for the first activity - but it is just for human consumption
-We don't want the computer to run these 2 lines - how can we solve this problem?
+We don't want the computer to run these 2 lines - how can we solve this problem?
+
+//We have to use the // to comment a single line
+/* or use /* to comment multiple lines */ 

Sprint-2/2-mandatory-errors/1.js

@@ -2,3 +2,5 @@
 
 const age = 33;
 age = age + 1;
+/* const means that the variable cannot be reassigned we should use let keyword instead.
+TypeError displayed due to that. */

Sprint-2/2-mandatory-errors/2.js

@@ -3,3 +3,8 @@
 
 console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+
+//The error we see it's a ReferenceError which tells us that we cannot access variable before initialization.
+
+/*JavaScript reads the code from top to bottom, order is wrong.
+Task cannot be executed as variable cannot be access before being created. */

Sprint-2/2-mandatory-errors/3.js

@@ -1,9 +1,15 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+const last4Digits = cardNumber.toString().slice(-4);
+console.log(last4Digits);
 
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working
 // Before running the code, make and explain a prediction about why the code won't work
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+
+/*The code would not work because cardNumber variable stores number data type and .slice() method cannot be used on a number,
+if we run the code without changing data type to string we will get TypeError displayed
+I used .toString() method to convert cardNumber variable to a string and then used .slice(-4) to get the last 4 digits. */

Sprint-2/2-mandatory-errors/4.js

@@ -1,2 +1,4 @@
 const 12HourClockTime = "8:53pm";
 const 24hourClockTime = "20:53";
+
+//A variable cannot start with a number, SyntaxError is displayed.