Object methods in JavaScript.

Question

where is this undefined thing coming from in my output?

code:
https://code.sololearn.com/WxmpE3RPBFJP/#js

output:
how are you doingundefined

Answer 1

Try this.
https://code.sololearn.com/WT3vC1k19xw8/?ref=app

Answer 2

you can check below link code where i have mention how your program works and give you a undefined in string https://code.sololearn.com/WzAqw1nYF7ok/?ref=app

Answer 3

output is hi

Answer 4

okay i understand this what you wrote. but what i don't understand is, if
function a()
{
document.write(31);}
var a = 'hi';
//as you said
var b = a;
what will get stored in b? function definition or variable a

Answer 5

whereas in this code i get an error that says a is not an function which clearly It is.
function a()
{
return 31;}
var a = 'hi';
//as you said
var b = a();
document.write(b);

Answer 6

but what about the second code, I'm clearly assigning var b = a(); which is a function. still i get an error which days a ain't a function

Answer 7

function a(){return 31;}
//var a = 'hi';//if you uncomment this line means you override the a in string from the function so a() gives error

var b = a;
document.write(b);

Answer 8

okay, so because var a comes after function a it overrides?

Answer 9

Where you have "{greet:hello()..."
"hello()" does not equal "hello".
"hello()" = the return value of the function hello.
As "hello()" does not return a value it will return undefined.

Answer 10

so basically you have to return basically something, and since nothing is getting returned, I'm getting undefined?

Answer 11

okay so Josh, i understand you did not put the function hello() in object as hello, you put it without braces, and in the method you put braces, although i don't understand why, but understand how i should proceed with the code.

Answer 12

kirtan, still, there's an alert which gives undefined.

Answer 13

please uncomment return statement and check again

Answer 14

your hello function returns nothing that's why

Answer 15

is it necessary to return something everytime in a function?

Answer 16

also if i uncomment that return statement, i get an unexpected Identifier error

Answer 17

can you review my code first

Answer 18

where is this undefined thing coming from in my output
? <-- your question is this. that's why i commented return statement in my code. :)☺️

Answer 19

// Created by Kshitij Shukla

function hello()
{
document.write("how are you doing");
return 'hi';
}
var hi={greet:hello()}
var x = hi.greet; // hello() called here and function return nothing to in x that's why undefined coming..
alert(x);
document.write(hi.greet);

Answer 20

okay i understood your code, i also understood how it works, can you please tell me how is it different from what josh did in the code he sent above? he put the () in method of the object and not the property's value