var or let
Hello everyone. Just wondering, I know it's a reference type, but just to clear some things up. What would had happened if the teacher had used a variable instead of a constant? It's the same result right? Or what is the difference?
Wouter WillebrandsiOS Development with Swift Techdegree Graduate 13,121 Points
It depends on the occasion what happens when a constant is changed to a variable, but in most cases this won't be a problem. However if you define something as a variable, but afterwards you are not mutating it in any way in your code, the compiler will suggest you change it into a constant (let) instead.
It is often good practice to define properties as constants, and change it to var if the compiler informs you that you're trying to mutate a constant, instead of the other way around. This prevents you from accidentally mutating a property that would allow your app to crash.
I hope this answers your question.