In JavaScript, can I use a ternary expression without the else part?

Question

I am pretty new to JavaScript and I am trying to make a little control flow example but it doesn't want to work because of multiple errors.For example on line 5 it says unexpected token:

let raceNumber = Math.floor(Math.random()*1000);
let registeredEarly = true;
const runnerAge = 21;

!registeredEarly ? raceNumber += 1000;

if(runnerAge > 18){
 console.log('You will race at 11:00AM with the racenumber ' + raceNumber);
} else if(registeredEarly === true || runnerAge > 18){
 console.log('Yu will race at 11:00am and your racenumber is ' + racenumber);
} else if(runnerAge < 18 && !regiteredEarly){
 console.log('You will race at 12:30pm and your racenumber is ' + racenumber);
} else{
 console.log('Pls register at the desk.');
};

Please explain to me what you did and why, I want to learn as much as possible!

So what do i do cant i just leave the else? i dont need one @Li357 — itsolidude, Dec 17 '17 at 00:49
Add the errors you get. And read the [tour] and [help] some time; your questions show no real understanding of how Stack Overflow works. — Jongware, Dec 17 '17 at 00:50
Why use a ternary operator if you don't need the else part ? — TGrif, Dec 17 '17 at 13:53

score 1 · Answer 1 · answered Dec 17 '17 at 00:49

1

It is expecting ":" after 1000, not ";"

 !registeredEarly ? raceNumber += 1000 : null ;

To answer your comment, no you can't skip the ":" (else), because the syntax requires it.

answered Dec 17 '17 at 00:49

Jim W

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In JavaScript, can I use a ternary expression without the else part?

1 Answers1