Complete all Key-Errors exercises

Author: ausiejute

Sprint-3/1-key-errors/0.js

@@ -1,13 +1,20 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============> If the function will be called, it will print the first letter of the string
+// in capital with the rest of the word in lowercase
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
-function capitalise(str) {
+/* function capitalise(str) {
   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
   return str;
+} */
+
+// =============> A SyntaxError was thrown because the str was used to name both the function parameter
+// and a new variable, which cannot happen in the same scope
+// =============>
+function capitalise(str) {
+  return `${str[0].toUpperCase()}${str.slice(1)}`;
 }
 
-// =============> write your explanation here
-// =============> write your new code here
+console.log(capitalise("mother"));

Sprint-3/1-key-errors/1.js

@@ -1,20 +1,28 @@
 // Predict and explain first...
+// There will be another syntax error, because the same name is used for both the parameter and the variable
+// (decimalNumber)
 
 // Why will an error occur when this program runs?
-// =============> write your prediction here
+// =============>
+// We cannot redeclare a variable with the same name in the same scope.
 
 // Try playing computer with the example to work out what is going on
 
-function convertToPercentage(decimalNumber) {
+/*function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
 
   return percentage;
 }
-
-console.log(decimalNumber);
-
+*/
 // =============> write your explanation here
+//
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
+
+console.log(convertToPercentage(0.8));

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

@@ -1,20 +1,23 @@
-
 // Predict and explain first BEFORE you run any code...
 
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// I predict it will say 'num is not defined'
 
-function square(3) {
-    return num * num;
-}
+//  function square(3) {
+//     return num * num;
+// }
 
 // =============> write the error message here
-
+// SyntaxError: Unexpected number
 // =============> explain this error message here
-
+// Instead of a parameter name, the actual value was passed, resulting in an error;
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
-
+function square(num) {
+  return num * num;
+}
+console.log(square(6));