function logItType(output) {
   console.log(typeof output, ";", output);
}

// this creates a temp variable for this name or this variable. 

function Person(name, ghID, classOf, gender) {
   this.name = name;
   this.ghID = ghID;
   this.classOf = classOf;
   this.gender = gender;
   this.role = "";
}

// define a setter for role in Person data
Person.prototype.setRole = function(role) {
   this.role = role;
}

// define a JSON conversion "method" associated with Person
Person.prototype.toJSON = function() {
   const obj = {name: this.name, ghID: this.ghID, classOf: this.classOf, role: this.role, gender: this.gender};
   const json = JSON.stringify(obj);
   return json;
}

// make a new Person and assign to variable teacher
var teacher = new Person("Mr M", "jm1021", 1977, "Male");  // object type is easy to work with in JavaScript
logItType(teacher);  // before role
logItType(teacher.toJSON());  // ok to do this even though role is not yet defined

// output of Object and JSON/string associated with Teacher
teacher.setRole("Teacher");   // set the role
logItType(teacher); 
logItType(teacher.toJSON());

object ; Person {
  name: 'Mr M',
  ghID: 'jm1021',
  classOf: 1977,
  gender: 'Male',
  role: '' }
string ; {"name":"Mr M","ghID":"jm1021","classOf":1977,"role":"","gender":"Male"}
object ; Person {
  name: 'Mr M',
  ghID: 'jm1021',
  classOf: 1977,
  gender: 'Male',
  role: 'Teacher' }
string ; {"name":"Mr M","ghID":"jm1021","classOf":1977,"role":"Teacher","gender":"Male"}

var students = [ 
   new Person("Amay Advani", "amayadvani", 2024, "Male"),
   new Person("Sarah Liu", "sarahliu", 2024, "Female"),
   new Person("Emma Shen", "e-shen2022", 2024, "Female"),
   new Person("Vivian Ni", "vivianknee", 2024, "Female"),
];

// define a classroom and build Classroom objects and json
function Classroom(teacher, students){ // 1 teacher, many student
   // start Classroom with Teacher
   teacher.setRole("Teacher");
   this.teacher = teacher;
   this.classroom = [teacher];
   // add each Student to Classroom
   this.students = students;
   this.students.forEach(student => { student.setRole("Student"); this.classroom.push(student); });
   // build json/string format of Classroom
   this.json = [];
   this.classroom.forEach(person => this.json.push(person.toJSON()));
}

// make a CompSci classroom from formerly defined teacher and students
compsci = new Classroom(teacher, students);

// output of Objects and JSON in CompSci classroom
logItType(compsci.classroom);  // constructed classroom object
logItType(compsci.classroom[0].name);  // abstract 1st objects name
logItType(compsci.json[0]);  // show json conversion of 1st object to string
logItType(JSON.parse(compsci.json[0]));

object ; [ Person {
    name: 'Mr M',
    ghID: 'jm1021',
    classOf: 1977,
    gender: 'Male',
    role: 'Teacher' },
  Person {
    name: 'Amay Advani',
    ghID: 'amayadvani',
    classOf: 2024,
    gender: 'Male',
    role: 'Student' },
  Person {
    name: 'Sarah Liu',
    ghID: 'sarahliu',
    classOf: 2024,
    gender: 'Female',
    role: 'Student' },
  Person {
    name: 'Emma Shen',
    ghID: 'e-shen2022',
    classOf: 2024,
    gender: 'Female',
    role: 'Student' },
  Person {
    name: 'Vivian Ni',
    ghID: 'vivianknee',
    classOf: 2024,
    gender: 'Female',
    role: 'Student' } ]
string ; Mr M
string ; {"name":"Mr M","ghID":"jm1021","classOf":1977,"role":"Teacher","gender":"Male"}
object ; { name: 'Mr M',
  ghID: 'jm1021',
  classOf: 1977,
  role: 'Teacher',
  gender: 'Male' }

Classroom.prototype._toHtml = function() {
  // HTML Style is build using inline structure
  var style = (
    "display:inline-block;" +
    "border: 2px solid grey;" +
    "box-shadow: 0.8em 0.4em 0.4em grey;"
  );

  // HTML Body of Table is build as a series of concatenations (+=)
  var body = "";
  // Heading for Array Columns
  body += "<tr>";
  body += "<th><mark>" + "Name" + "</mark></th>";
  body += "<th><mark>" + "GitHub ID" + "</mark></th>";
  body += "<th><mark>" + "Class Of" + "</mark></th>";
  body += "<th><mark>" + "Role" + "</mark></th>";
  body += "<th><mark>" + "Gender" + "</mark></th>";
  body += "</tr>";
  // Data of Array, iterate through each row of compsci.classroom 
  for (var row of compsci.classroom) {
    // tr for each row, a new line
    body += "<tr>";
    // td for each column of data
    body += "<td>" + row.name + "</td>";
    body += "<td>" + row.ghID + "</td>";
    body += "<td>" + row.classOf + "</td>";
    body += "<td>" + row.role + "</td>";
    body += "<td>" + row.gender + "</td>";
    // tr to end line
    body += "<tr>";
  }

   // Build and HTML fragment of div, table, table body
  return (
    "<div style='" + style + "'>" +
      "<table>" +
        body +
      "</table>" +
    "</div>"
  );

};

// IJavaScript HTML processor receive parameter of defined HTML fragment
$$.html(compsci._toHtml());

Name	GitHub ID	Class Of	Role	Gender
Mr M	jm1021	1977	Teacher	Male
Amay Advani	amayadvani	2024	Student	Male
Sarah Liu	sarahliu	2024	Student	Female
Emma Shen	e-shen2022	2024	Student	Female
Vivian Ni	vivianknee	2024	Student	Female