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JavaScript

Can someone please explain what 'this' is actually referring to in Media.call(this, title, duration);?

Can someone please explain what 'this' is actually referring to in Media.call(this, title, duration);?

I've read all the questions and answers among the video in this thread and have looked elsewhere on the web and it still isn't clear. Can someone please break it down in a simpler way? Andrew's way of teaching is failing me once again....

2 Answers

this in this instance is the Song (or Video) object being constructed. We are calling Media(title, duration) but also telling it that the this inside Media() should be the very same object that this is inside Song().

Thank you.

However, why is Andrew removing this.isPlaying from the Song object constructor? I don't understand how the Song object constructor inherits this.isPlaying from the Media.call() if it's not used as one of the parameters?

The object you create will have all the properties given to it by both Song() and Media(). Since isPlaying is set in Media() to a default value of false, it doesn't need to passed in.

Thank you for the explanation!