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Shaun Kelly
5,648 PointsUnderstanding constants?
Can anybody explain what the definition of constants are and provide any kind of further documentation about it ? From my understand it's a bit like property's..
1 Answer
Jayden Spring
8,625 PointsIts quite simple to its precisely that "constant" - i.e something that is a constant won't change. If you open a playground, create a constant (let) = "Hello" and then try and append to the string and you will get an error.
Where constants are very useful is when you are declaring/initialising a class or structure. If you think about it when you create youre instance of said class/structure, you don't want it necessarily to be mutated later on in the program. As a simple example (very very simple);
var myClass = "Hello Class"
let myclass = MyClass();
myclass.doSomething(withSomeProperty);
myclass = "New Class"
Say you have a VARIABLE which you put the 'name' of the class you are accessing in and the class itself in a similar name as well (youll notice one is capitalised one is not). If at some point you tried to change myclass instead of the string myClass the compiler would throw an error. However, you are still able to access instance methods of the class and/or structure.