Shorthand only for if

Question

How can I write shorthand for an IF statement without else?

var val = score == 10 ? win;
console.log(val) //basically I want to update `val` only with the if statement.

Check http://alvinalexander.com/java/edu/pj/pj010018 – KernelPanic Dec 10 '15 at 08:06 — KernelPanic, Dec 10 '15 at 08:06
and what should assigned if not? – Nina Scholz Dec 10 '15 at 08:07 — Nina Scholz, Dec 10 '15 at 08:07
@NinaScholz if not shouldn't update `val` at all. – Becky Dec 10 '15 at 08:08 — Becky, Dec 10 '15 at 08:08

score 3 · Accepted Answer · answered Dec 10 '15 at 08:10

3

You can use a logical and:

var val;
score == 10 && (val = win);

answered Dec 10 '15 at 08:10

Nina Scholz

2

@Becky: This functions and is an answer to your question, but it's **awful**. (Which is not Nina's fault.) Just use an `if`. Side note: No need for the `()`. – T.J. Crowder Dec 10 '15 at 08:13
1

Downvoter: This answers the question that was asked, usefully. Don't vote because you don't like the style. – T.J. Crowder Dec 10 '15 at 08:15
@T.J.Crowder Thanks for your comment. What makes you say this answer is awful? – Becky Dec 10 '15 at 08:15
1

@Becky: Not the *answer*, just this usage of `&&` (which sadly some people do). It's a flat-out abusage. Hard to read, hard to debug. But that's just opinion. :-) – T.J. Crowder Dec 10 '15 at 08:16
@T.J.Crowder Understood. Thanks. But it answers the question perfectly. – Becky Dec 10 '15 at 08:18
@T.J.Crowder Looks like `()` is required to avoid the `:` ternary operator error. – Becky Dec 10 '15 at 08:21
1

the `()` are required, because the assignment throws a `syntax error` – Nina Scholz Dec 10 '15 at 08:28
1

@NinaScholz: Gah, precedence, you're right. – T.J. Crowder Dec 10 '15 at 08:38

gurvinder372 · Answer 2 · 2015-12-10T08:12:17.867

1

why not simply

var val = score == 10 ? win : val;

or

var score = 10, val=10, win=11;
score == 10 && ( val = win )
alert( val ); //after this output will be 11

edited Dec 10 '15 at 08:12

answered Dec 10 '15 at 08:08

gurvinder372

That's cool. Never thught of doing `: val;`. Thanks :) +10 – Becky Dec 10 '15 at 08:11

Jacques Marais · Answer 3 · 2015-12-10T08:15:51.493

0

Well, if it shouldn't update the val variable if the statement doesn't return true, just use the val variable as the else:

var val = score == 10 ? win: val;
console.log(val)

You could also use:

score == 10 && var val = win;

But I would suggest just using the if statement for readability:

if(score == 10) 
    var val = win;

edited Dec 10 '15 at 08:15

answered Dec 10 '15 at 08:09

Jacques Marais

3 Answers3