raziqali

src/exercises/1/exercise.js

@@ -3,7 +3,14 @@
 //  - Fix the issue.
 
 function printOneToTen() {
-  for (const number = 1; number <= 10; number++) {
+  // Error : we can't change const variable in js 
+  // for (const number = 1; number <= 10; number++) {
+
+  // Fix: change const to let
+  for (let number = 1; number <= 10; number++) {
     console.log(`\n${number}`);
   }
 }
+
+// we need to call the function to get the Output.
+printOneToTen()

src/exercises/10/exercise.js

@@ -15,4 +15,29 @@
 		}
 	]
 */
-function findVoteEligibleCandidates(populationList) {}
+function findVoteEligibleCandidates(populationList) {
+    console.log(populationList.filter((entry) => entry.age >= 18).map((entry => entry.name)))
+
+    // it can also be done as follow: 
+    // console.log(populationList.forEach((entry) => {
+    //     entry.age >= 18 ? console.log(entry.name) : null
+    // }))
+
+    // NOTE: filter and map returns the list. whereas, forEach doesn't return anything.
+    // if we need to save the result we can use filter/map not foreach
+}
+
+findVoteEligibleCandidates([
+    {
+        name:"Ravi",
+        age:28
+    },
+    {
+        name:"Teja",
+        age:18
+    },
+    {
+        name:"Spider-man",
+        age:17
+    }
+])

src/exercises/11/exercise.js

@@ -2,4 +2,12 @@
 // - Use Array methods
 // - Do not use loops
 
-function sumOfArray(inputArray) {}
+function sumOfArray(inputArray) {
+    let sum = 0;
+    inputArray.forEach(element => {
+        sum += element;
+    });
+    console.log(sum);
+}
+
+sumOfArray([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);

src/exercises/12/exercise.js

@@ -5,5 +5,12 @@ function errorFunction() {
 }
 
 function errorCaller() {
-  errorFunction();
+  try {
+      errorFunction();
+  }
+  catch(e) {
+      console.log(e);
+  }
 }
+
+errorCaller();

src/exercises/13/exercise.js

@@ -5,6 +5,15 @@ const employee = {
   lastName: "Teja",
   age: 29,
   id: 1122,
-  getFullName: function () {},
-  checkVoteEligiblity: function () {},
+  getFullName: function () {
+      return `${this.firstName} ${this.lastName}`;
+  },
+  checkVoteEligiblity: function () {
+      return this.age >= 18;
+  },
 };
+
+
+
+console.log(employee.getFullName());
+console.log(employee.checkVoteEligiblity());

src/exercises/14/exercise.js

@@ -1,17 +1,26 @@
 // Get the full name of the new employee. See how you can execute the function "getFullName" on newEmployee object.
-// - Comment your findings
+// // - Comment your findings
 
 const employee = {
   firstName: "Ravi",
   lastName: "Teja",
   age: 29,
   id: 1122,
   getFullName: function () {
-    //Copy the solution from the exercise before this.
+      //Copy the solution from the exercise before this.
+      if(arguments.length > 0) {
+          return `${arguments[0].firstName} ${arguments[0].lastName}`;
+      }
+      else {
+          return `${this.firstName} ${this.lastName}`;
+      }
   },
 };
 
 const newEmployee = {
   firstName: "New",
   lastName: "Employee",
 };
+
+console.log(employee.getFullName())
+console.log(employee.getFullName(newEmployee))

src/exercises/15/exercise.js

@@ -1,13 +1,16 @@
 // Convert the below functions into arrow functions.
 
-const greetings = function () {
+const greetings = () => {
   return "Hello World";
 };
 
-const isEven = function (num) {
+const isEven = (num) => {
   if (num % 2 == 0) {
     return true;
   } else {
     return false;
   }
 };
+
+console.log(greetings)
+console.log(isEven)

src/exercises/16/exercise.js

@@ -2,6 +2,40 @@
 // - Identify the class variables
 // - Create function for all the possible functionalities.
 
-class Leave {
+// exporting class to be able to import in next exercise.
+export class Leave {
   //...
+  constructor(name, reason, startDate, endDate) {
+    this.name = name;
+    this.reason = reason;
+    this.startDate = startDate;
+    this.endDate = endDate ? endDate : startDate;
+    this.status = false;
+  }
+
+  showLeaveDetails() {
+    console.log(`---- ` + (this.status ? 'granted' : 'not yet granted') + ` ----`)
+    if(this.startDate === this.endDate) {
+      console.log(`${this.name} kept leave on ${this.startDate} for ${this.reason}.\n`);
+    }
+    else {
+      console.log(`${this.name} kept leave from ${this.startDate} to ${this.endDate} for ${this.reason}\n`);
+    }
+
+  }
+
+  grantLeave = function(){
+    this.status = true;
+    console.log(`GRANTED LEAVE TO ${this.name.toUpperCase()}\n`);
+  }
 }
+
+let johnLeave = new Leave("John", "marriage", "17/11/2022", "20/11/2022");
+let raniLeave = new Leave("Rani", "anniversary", "18/11/2022");
+
+johnLeave.showLeaveDetails();
+raniLeave.showLeaveDetails();
+
+johnLeave.grantLeave();
+
+johnLeave.showLeaveDetails();

src/exercises/17/exercise.js

@@ -1 +1,24 @@
 // Extend the Leave class, to create different classes for different Leave types.
+
+// imports Leave class from last exercise
+import { Leave } from '../16/exercise'
+
+class CasualLeave extends Leave {
+    constructor(name, startDate, endDate) {
+        super(name, "Holiday", startDate, endDate)
+    }
+}
+
+
+class SickLeave extends Leave {
+    constructor(name, startDate, endDate) {
+        super(name, "sick", startDate, endDate)
+    }
+}
+
+
+let johnLeave = new CasualLeave("John", "17/11/2022", "20/11/2022");
+let raniLeave = new SickLeave("Rani", "18/11/2022");
+
+johnLeave.showLeaveDetails();
+raniLeave.showLeaveDetails();

src/exercises/17/index.html

@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html>
+    <head>
+    </head>
+    <body>
+        <h1>Hello</h1>
+        <script type="module" src="./exercise.js"></script>
+        <script type="module" src="../16/exercise.js"></script>
+
+    </body>
+</html>

src/exercises/18/exercise.js

@@ -1,3 +1,33 @@
 // Use Javascript modules to create seperate files for each of the Leave type classes.
 // - Comment your understanding about import
 // - Comment your understanding about export
+
+
+/**
+ * :: IMPORT/EXPORT ::
+ * 
+ * to use js import/export we need to make scripts as modules
+ * for this we can either use package.json({type: module}) or a HTML file(include scripts and define type="module") to define the type as 'module'
+ * we can export and import - functions, classes, constants etc...
+ * Import & Export (using index.html)
+ * we can do a _simple export_ lets say, 
+ * -  export class ClassName {...} 
+ * then we  can import it as 
+ * -  import { ClassName } from '../fileDirectory'
+ * 
+ * for example, 
+ * Utils.js
+ *   export function fun1{...}
+ *   export function fun2{...}
+ * Diff.js
+ *   import {fun1, fun2} from './Utils.js'
+ * 
+ * 
+ * Or we can do default export like
+ * - export default class ClassName {...}
+ * - import ClassName from './path'
+ * 
+ * Import & Export (using package.json ES-6 modules)
+ * module.export = { ...list }
+ * require('../path') -> this will return so we need to save it in a var inorder to use it( const importName = require('../path')  )
+ */

src/exercises/19/exercise.js

@@ -1,3 +1,14 @@
 // Comment below what did you understand from the previous 3 exercises about
 // - prototype
 // - __proto__
+
+/**
+ * for every class Prototype is a default entry we have
+ * its like a blueprint of the object
+ * and __proto__ gives the prototype of the prototype of object
+ * we can add methods to prototype as follows
+ * - Book.prototype.getDetails = function() { ... }
+ * when we console.log any object of Book class it has prototype(even if the object is empty i.e {})
+ * and we have this new getDetails function in Book.prototype
+ * These have Object methods like constructor, hasOwnProperty etc... along with getter and setter.
+ */

src/exercises/2/exercise.js

@@ -3,11 +3,18 @@
 //  - Fix the issue.
 
 function divideTenByNumber(number) {
+  // Error: result is inside the local space of if and else blocks. So, scope of result is limited to only those blocks.
+  // Fix: move result above condition statement
+
+  let result;
   if (number != 0) {
-    let result = 10 / number;
+    result = 10 / number;
   } else {
-    let result = "Indeterminate";
+    result = "Indeterminate";
   }
 
   console.log(`Result after dividing 10 by ${number} is ${result}`);
 }
+
+
+divideTenByNumber(0);

src/exercises/20/exercise.js

@@ -1,3 +1,18 @@
 // What is debugger;
 // - Comment your understanding of it.
 // - Paste the link of the MDN article here.
+
+
+/**
+ * Debugger is a keyword in js
+ *      - debugger
+ * it invokes all the debugging functionalities if present.
+ * we can use it like a breakpoint to stop the execution at the given point.
+ * and if any debugger methods are available it runs those functions and then it continues execution 
+ * if no debugger functions are available then it has no effect.
+ * this helps to find particularly in which statement does the bug is appearing.
+ * 
+ * MDN link: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/debugger
+ * W3Schools: https://www.w3schools.com/js/js_debugging.asp
+ * 
+ */

src/exercises/21/exercise.js

@@ -1 +1,32 @@
 // What are the different levels of logs and how do we print them to the console?
+
+/**
+ * Different levels of logs are,
+ * TRACE: trace gives full visibility of what is happening inside the application
+ *  - console.trace('hey')
+ * DEBUG: handles logging of information that needed to be diagnosed.
+ *  - console.debug('hey')
+ * INFO: it is just informative. it can be used to give information about the steps that passed smoothly may be in an algorithm.
+ *  - console.info('hey')
+ * WARN: used to warn about unexpected scenarios that may occurs without actually intrupting the controlflow of the program
+ *  - console.warn('hey')
+ * ERROR: used to give error messages that oocured
+ *  - console.error('hey')
+ * FATAL: it gives the critical information like operation fail which is required to move forward ( unable to connect server )
+ *  - console.fatal('hey')
+ * 
+ * the one that is widely used is console.log() -> used to print info about anything that occurs in our program. can be used for all levels of logs.
+ */
+
+
+
+ console.trace("Hey!");
+ console.debug("Hey!");
+ console.info("Hey!");
+ console.warn("Hey!");
+ console.error("Hey!");
+ console.fatal("Hey!");
+
+
+ console.log("Hey!")
+

src/exercises/22/exercise.js

@@ -5,9 +5,23 @@
 function randomCalculator() {
   let x = 10,
     y = 0;
+    debugger;
   x = x * 10 + 1 - (2 / 2) * 3;
   y = x - 1 + 3 * 10 - 2;
   x = x * 2 - (1 / 3) * 3;
   x = x + 10 - 2 - 3 * 2;
   console.log(x);
 }
+
+/**
+ * Initially add x and y variables to Watch section in Chrome debugging console.
+ * and in code add a debugger statement below first line so that we can track x and y values from intial position
+ * if added at the top they will not be created and it shows '< not available >'
+ * now reload the page it will automatically stop the execution at debugger statement in line8.
+ * and then click on `ctrl + '` to go step by step and track x and y values after each statement.
+ * also observe that after executing console.log we get the last x value logged in console.
+ */
+
+
+
+randomCalculator()

src/exercises/22/index.html

@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Document</title>
+</head>
+<body>
+    <script src="./exercise.js"></script>
+</body>
+</html>