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iOS Object-Oriented Swift Properties Optional Property

Posted by Leonardo Santos
Leonardo Santos
5,290 Points

Changing the value of a constant

We learned in past lessons that a value of object instantiated with "let" keyword can't be changed. It would be a constant.

But in this lesson, we initialised toy with "let" and after, we changed the value of "batteries" property.

Why can we change the value of the toy's property if it is instantiated with "let'?

let toy = Electronic(title: "RC Car", price: 79) 
toy.batteries = true

3 Answers

Holger Liesegang
Holger Liesegang
50,595 Points
Holger Liesegang
Holger Liesegang
50,595 Points

Hi Leonardo!

You are right, one can't change the value of a constant but while you can't assign another object to the constant toy you can still make use of all the properties of this (constantly assigned) object :)

Liam Herbert
Liam Herbert
15,140 Points
Liam Herbert
Liam Herbert
15,140 Points

Is there a question your are hoping to have answered here??? I do not understand what it is you are trying to ask.

Leonardo Santos
Leonardo Santos
5,290 Points

Why can we change the value of the toy's property if it is instantiated with "let'?

Leonardo Santos
Leonardo Santos
5,290 Points
Leonardo Santos
Leonardo Santos
5,290 Points

Thanks, Holger. I hadn't realised that the fact that an object is constant does not automatically apply to its properties.