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iOS Swift 2.0 Basics Swift Operators Working With Operators: Part 2

Lana Wong
Lana Wong
3,968 Points
Posted by Lana Wong
Lana Wong
3,968 Points

Preview Does not Work

My code does not seem to work when I press PREVIEW, but when I press CHECK WORK, it says the code is correct. So there is nothing wrong with my code. Why is the PREVIEW button not work?

operators2.swift 
var initialScore = 8

let totalScore = ++initialScore

let isWinner = totalScore != 10

1 Answer

Derek Scollon
Derek Scollon
8,422 Points

The preview works but usually just shows errors so the output is usually blank if your code compiles correctly. Just to try it out, try entering this...

var initialScore = 8

let totalScore = ++initialScore

let isWinner = totalScore != 10

let isWinner = false

...and look at the preview. Since this code is trying to declare the isWinner constant twice, this is an error and the preview will show you this.