am currently on “inheritance in JS” and i got to the point where am supposed to inherit Student from Person but whenever i call the greeting function on student, it tells me
TypeError: Student.greeting is not a function
i know TypeError occurs when the value is not the expected type but i cant seem to find that value this is the code for student
function Person(first, last, age, gender, interests) {
this.name = {
first,
last
};
this.age = age;
this.gender = gender;
this.interests = interests;
};
Person.prototype.bio = function() {
// First define a string, and make it equal to the part of
// the bio that we know will always be the same.
let string = this.name.first + ' ' + this.name.last + ' is ' + this.age + ' years old. ';
// define a variable that will contain the pronoun part of
// the second sentence
let pronoun;
// check what the value of gender is, and set pronoun
// to an appropriate value in each case
if(this.gender === 'male' || this.gender === 'Male' || this.gender === 'm' || this.gender === 'M') {
pronoun = 'He likes ';
} else if(this.gender === 'female' || this.gender === 'Female' || this.gender === 'f' || this.gender === 'F') {
pronoun = 'She likes ';
} else {
pronoun = 'They like ';
}
// add the pronoun string on to the end of the main string
string += pronoun;
// use another conditional to structure the last part of the
// second sentence depending on whether the number of interests
// is 1, 2, or 3
if(this.interests.length === 1) {
string += this.interests[0] + '.';
} else if(this.interests.length === 2) {
string += this.interests[0] + ' and ' + this.interests[1] + '.';
} else {
// if there are more than 2 interests, we loop through them
// all, adding each one to the main string followed by a comma,
// except for the last one, which needs an and & a full stop
for(let i = 0; i < this.interests.length; i++) {
if(i === this.interests.length - 1) {
string += 'and ' + this.interests[i] + '.';
} else {
string += this.interests[i] + ', ';
}
}
}
// finally, with the string built, we alert() it
alert(string);
};
Person.prototype.greeting = function() {
alert('Hi! I\'m ' + this.name.first + '.');
};
Person.prototype.farewell = function() {
alert(this.name.first + ' has left the building. Bye for now!');
}
let person1 = new Person('Tammi', 'Smith', 17, 'female', ['music', 'skiing', 'kickboxing']);
// teacher
function Teacher(first, last, age, gender, interests, subject) {
Person.call(this, first, last, age, gender, interests);
this.subject = subject;
}
Teacher.prototype = Object.create(Person.prototype);
Object.defineProperty(Teacher.prototype, 'constructor', {
value: Teacher,
enumerable: false, // so that it does not appear in 'for in' loop
writable: true
});
Teacher.prototype.greeting = function() {
let prefix;
if (this.gender === 'male' || this.gender === 'Male' || this.gender === 'm' || this.gender === 'M') {
prefix = 'Mr.';
} else if (this.gender === 'female' || this.gender === 'Female' || this.gender === 'f' || this.gender === 'F') {
prefix = 'Ms.';
} else {
prefix = 'Mx.';
}
alert('Hello. My name is ' + prefix + ' ' + this.name.last + ', and I teach ' + this.subject + '.');
};
let teacher1 = new Teacher('Dave', 'Griffiths', 31, 'male', ['football', 'cookery'], 'mathematics');
// Student
function Student(first, last, age, gender, interests) {
Person.call(this, first, last, age, gender, interests);
}
Student.prototype = Object.create(Person.prototype);
Object.defineProperty(Student.prototype, 'constructor', {
value: Student,
enumerable: false,
writable: true
});
Student.prototype.greeting = function() {
alert('Yo! am ' + this.name.first + ' and i am a student.');
};
let student1 = new Student('lekan', 'ade', 24, 'male', ['coding', 'reading']);`