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Jonathan Hector
5,225 PointsFunny enough you can always override a constant if you don't assign a value to it.
let exampleBool : Bool
let number1 : Int = 1
let number2 : Int = 2
if(number1 > number2){
exampleBool = false
} else {
exampleBool = true
} //should always be false but you can play around with it.
print(exampleBool)
SivaKumar Kataru
2,386 PointsWell its not over riding a CONSTANT value . You created a constant( exampleBool ) without initializing any value to it .When you declare a constant/variable without initializing any value to it , then the variable/constant contains garbage values . And in the IF ELSE control flow , either IF or ELSE block may be executed . So therefore the uninitialized constant may be initialized with the value of true/false based on the evaluation of IF ELSE block only once.
2 Answers
SivaKumar Kataru
2,386 PointsTo, Stephen Emery ........................................ let exampleBool: Bool let firstValue:Int = 1 let secondValue:Int = 2 if(firstValue > secondValue){ // This Line Won't Be executed at all . exampleBool = false } if (firstValue < secondValue){ // This Line will be executed . Therefor Let constant will be assigned with True . And Now it is Locked .so that you cant change further forever exampleBool = true }
Jabes Pauya
Courses Plus Student 2,432 Pointsfor the first place the first constant has no assigned value let exampleBool : Bool = ? has no assigned value yet
until such time you added a condition to check the values of number1 and number2 if the condition satisfied either condition that is the time when your constant exampleBool will have assigned value (true/false)
as we studied in basic iOS, the variable is the only thing you can override the value like :
var String greeting = "Hello Linda"; greeting = "You forgot your glasses" - in this case the value has been override
Stephen Emery
14,384 PointsStephen Emery
14,384 PointsIt's not technically overriding a constant if you leave it unassigned/unitialized. You create an uninitialized constant at the start. Then you assign a value to it with your if statement. Since it's an if/else statement, only one of two possibilities will ever happen. You don't get an compiler error, because only 1 assignment could ever happen. If you write the code like I did below, you will get a compiler error.
let exampleBool : Bool let number1 : Int = 1 let number2 : Int = 2
if(number1 > number2){ exampleBool = false } if(number1 < number2) { exampleBool = true //Immutable value 'exampleBool' may only be initialized once }