JavaScript error corrections

Author: fromonda

Sprint-1/2-mandatory-errors/0.js

@@ -1,2 +1,10 @@
 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?
+
+//The error message displayed by Node.js is:
+//Uncaught SyntaxError: Unexpected identifier 'is'
+//This is a syntax error. It occurs because JavaScript is trying to interpret an
+//English sentence as JavaScript code. After reading the word 'This', the JavaScript
+//parser expects a valid JavaScript operator. Instead, it encounters another variable
+//name, 'is', which is not valid in that position according to JavaScript's syntax rules.
+//As a result, the parser throws the error Unexpected identifier 'is'.

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

@@ -2,3 +2,7 @@
 
 const age = 33;
 age = age + 1;
+
+//The error message displayed by Node.js is:
+//Uncaught TypeError: Assignment to constant variable
+//The error happens because const creates a variable whose value cannot be reassigned.

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

@@ -1,5 +1,9 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
-// what's the error ?
+// what's the error?
 
 console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+
+//The error message displayed by Node.js is:
+//Uncaught ReferenceError: cityOfBirth is not defined
+//The error occurs because the variable 'cityofBirth' is used before it has been declared.

Sprint-1/2-mandatory-errors/3.js

@@ -1,9 +1,14 @@
-const cardNumber = 4533787178994213;
+const cardNumber = "4533787178994213";
 const last4Digits = cardNumber.slice(-4);
 
-// 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
+// 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
+// Then try updating the expression last4Digits is assigned to, in order to get the correct value.
+
+//The error message displayed by Node.js is:
+//Uncaught TypeError: cardNumber.slice is not a function
+//The error occurs because slice() is a string method, but the variable 'cardNumber' is a number.
+//To get the last four digits, the number must be converted to a string.

Sprint-1/2-mandatory-errors/4.js

@@ -1,2 +1,6 @@
 const 12HourClockTime = "8:53pm";
 const 24hourClockTime = "20:53";
+
+//The error message displayed by Node.js is:
+//Uncaught SyntaxError: Invalid or unexpected token
+//This error happens because JavaScript does not allow variable names to start with a number.