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JavaScript Practice Object Interaction Checking Out and Returning a Book Demo: Checking Out and Returning a Book

Object recursion?

At around 01:30 in the video, we can see a Patron object in the console log. That object has a currentBook property, whose value is a Book object. That Book object hast itself a patron property, which references the same Patron object.

If I continue inspecting the properties, the patron -> currentbook -> patron -> currentbook pattern never ends. Are those just references pointing to the same unique two objects (patron and book)? Or are they actually copies of the same objects over and over? I assume it's the first explanation, otherwise the script would consume a lot of RAM, but I wanted to confirm.

2 Answers

Steven Parker
Steven Parker
224,849 Points

You're exactly right. Each object contains references to the other object, not copies of it.

Everton Carneiro
Everton Carneiro
15,994 Points

I don't believe that this is a memory leak type of situation, if it is what you are asking. In fact, you have the Book object and Patron object pointing to each other like this: Patron -><- currentBook, which is fine. For example, if you are modeling a graph or a doubly linked list you will need to have parent and child nodes pointing to each other.