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javascript double question mark

Lazurite answered on March 11, 2020 Popularity 10/10 Helpfulness 3/10

answer javascript double question mark

javascript double question mark

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let a = null;
const b = a ?? -1;		// Same as b = ( a != null ? a : -1 );
console.log(b);		  	// output: -1
//OR IF
let a = 9;
const b = a ?? -1;
console.log(b);  		// output: 9

//PS.,VERY CLOSE TO '||' OPERATION IN FUNCTION, BY NOT THE SAME

Popularity 10/10 Helpfulness 3/10 Language javascript

Source: Grepper

Tags: double javascript

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Contributed on Mar 11 2020

Lazurite

0 Answers Avg Quality 2/10

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double question mark javascript

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//Similar to || but only returns the right-hand operand if the left-hand is null or undefined
0 ?? "other" // 0
false ?? "other" // false
null ?? "other" // "other"
undefined ?? "other" // "other"

Popularity 10/10 Helpfulness 5/10 Language javascript

Source: Grepper

Tags: double do

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Contributed on May 20 2020

TC5550

0 Answers Avg Quality 2/10

double question mark javascript

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Nullish coalescing operator (??)
returns its right-hand side operand when its left-hand side operand is null or undefined, 
and otherwise returns its left-hand side operand.
const foo = null ?? 'default string';
console.log(foo);
// expected output: "default string" because left hand side is null.

const baz = 0 ?? 42;
console.log(baz);
// expected output: 0 , because left hand side ( 0 )  is not null or undefinded.

Popularity 10/10 Helpfulness 5/10 Language javascript

Source: developer.mozilla.org

Tags: double do

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Contributed on Sep 28 2022

Mujtaba Tarar

0 Answers Avg Quality 2/10

double question mark javascript

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b = a ?? -1
_____________
if(a != null){
	b = a;
}
else{
	b = -1;
}

Popularity 10/10 Helpfulness 2/10 Language javascript

Source: Grepper

Tags: double do

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Contributed on Apr 30 2022

okon1230

0 Answers Avg Quality 2/10

javascript double question mark

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double question mark javascript

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