Can someone explain this code, please?

Question

function abc (a) {
return (function(y){
return(y+1);})
(++a)+a+a;
}
alert(abc(2))

Answer 1

function abc (a) {

return (function(y){

return( y+1 ); } )
// y is 2, so... y + 1 = 3

( ++a ) +a +a;
// ++a = 4 + a + a ===> 4 + 3 + 3
// ++a = 4 because "a" is now 3, like "y"

}

alert(abc(2))

// I found this solution and it works, but i'll wait an expert opinion about it.

Answer 2

Because you passed 2 as argument in the call of abc( ) function.

alert( abc(2) )

Answer 3

something interesting happens here

you return the calling of a function

1) 2 is passed to abc
2) returning function(...){function body}(...) calls it
3) passing ++a increments a, passing the value 3
4) the inner function returns 3+1 (4)
5) return 4+a+a
6) what is the value of a after ++a?
7) that's right! 3
8) return 4+3+3
9) ????
10) profit!!!!

Answer 4

Ahhhhhhh @Burey what a whole world explaination

Answer 5

.... it is quiet advance javascript
This trick can explain how the whole jQuery work....
What did I say?
Well....This code is like as...

function abc (a) {
return (function(y){
return( y+1 ); } )(a++)+a+a
}
alert(abc(2))

Try
(function(a){document.write(a)})(1)
That will print 1 to screen...
Now try the other one
var a = function(i){document.write(i)};
a();

"if () along the function.that function will be executed"
That is how setInterval(function(){},0) work

Answer 6

hehe....kinda hard to explain it.....

Answer 7

A breakdown with pretty printing.
I understand if my way doesn't help, but worth a try.

https://code.sololearn.com/WxTEI1rejx0I/?ref=app

Answer 8

It was very hard to understand this code, but i finnally made it!) And now it looks simple...😊 One more time thanks to everyone!

Answer 9

Thank's for everyone! I will try to understand what you write, because I also have some problems with english))

Answer 10

I think like you too. But i don't understand why y = 2?