Is this the correct way for class inheritance within Javascript?

Question

Can someone confirm if the bellow script is indeed the correct way for class inheritance within Javascript?

WRONG WAY

var Person = function () {
   this.className = this.constructor.toString().match(/^function ([a-z_0-9]+)\(/i)[1];
   console.log( this.className ); //ERROR
}

var Mark = function () {
   Person.call(this);
}

Mark.prototype             = Object.create( Person.prototype );
Mark.prototype.constructor = Mark;

new Person; // I LIKE TO DISPLAY 'Person'
new Mark; // I LIKE DISPLAY 'Mark'

CORRECT WAY

function Person () {
   this.className = this.constructor.toString().match(/^function ([a-z_0-9]+)\(/i)[1];
   console.log( this.className );
}

function Mark () {
   Person.call(this); // Class Mark extend Person
}

Mark.prototype             = Object.create( Person.prototype );
Mark.prototype.constructor = Mark;

function Matteo () {
    Mark.call(this); // Class Matteo extend Mark
}

Matteo.prototype             = Object.create( Mark.prototype );
Matteo.prototype.constructor = Matteo;

new Person; // Displays: 'Person'
new Mark; // Displays: 'Mark'
new Matteo; // Display: 'Matteo'

possible duplicate of [Javascript get Function Name?](http://stackoverflow.com/questions/2648293/javascript-get-function-name) — Hexaholic, May 06 '15 at 09:31
Which variable name are you looking to print? The name of the function itself? — David Hoelzer, May 06 '15 at 09:33
Those names are variables, that are assigned after the function was parsed. They hold an anonymous function as their value – but this is not the same as a function name. See also: https://kangax.github.io/nfe/ — feeela, May 06 '15 at 09:35

Matteo Tassinari · Answer 1 · 2015-05-06T10:43:40.493

3

This works for me:

function Person () {
  console.log(this.constructor.toString().match(/^function ([a-z_0-9]+)\(/i)[1]);
}

function Mark () {
  Person.call(this);
}

function Matteo() {
  Mark.call(this);
}

new Person(); // "Person"
new Mark(); // "Mark"
new Matteo(); // "Matteo"

edited May 06 '15 at 10:43

answered May 06 '15 at 09:38

Matteo Tassinari

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Thanks for the contribution, could you answer the new question? – Mark May 06 '15 at 10:01

Is this the correct way for class inheritance within Javascript?

1 Answers1