unexpected output from arrow function

Question

I have following arrow function.

var a = 10;
var b = 5;
var str = (a,b) => ("sum: "+(a+b));

str();

I expected the output to be

sum: 15

but the output is

sum: NaN

why?

Q2x13 · Accepted Answer · 2017-01-12 07:02:31Z

2

var a = 10;

var b = 5;

var str = (a, b) => ("sum: " + (a + b));

str(a, b); // You have to call the function with parameters.

answered Jan 11, 2017 at 5:33

Q2x13

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Comments

Sandeep Nayak · Accepted Answer · 2017-01-11 05:31:01Z

1

You are not passing the arguments a and b in call to function

var a = 10;
var b = 5;
var str = (a, b) => ("sum: " + (a + b));
console.log(str(a, b));

answered Jan 11, 2017 at 5:31

Sandeep Nayak

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Max · Accepted Answer · 2017-01-11 05:30:51Z

1

You have to pass parameters str(a,b).

var a = 10;
var b = 5;
var str = (a,b) => ("sum: "+(a+b));

str(a,b);

answered Jan 11, 2017 at 5:30

Max

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