ES6 and Typescript Tutorial - 13 - Rest Operator

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[alter-ego-]

Thank you. This also implies there is no function overloading in javascript, right?

[premg]

thanks, video title should be named as Rest parameters

[gowthamdanthuluri]

What is the use of this rest and spread operator in real time environment

[PradumnyaGhadole]

Those who are getting errors at function parameters
In your tsconfig.json file set the parameter "noImplicitAny": false

[vigneshgvs]

'arguments' vs ...colors
no function overloading in javascript

[nishantdwivedi]

error TS2554: Expected 0 arguments, but got 1.

[yasirasarudheen]

My code :-
let displayColors = function(){
console.log(message);
for(let i in arguments){
console.log(arguments[i]);
}
}


let message = "List of Colors";


displayColors('Red');
displayColors('Red', 'Blue');
displayColors('Red', 'Blue', 'Green');


output:-
List of Colors
Red
List of Colors
Red
Blue
List of Colors
Red
Blue
Green
My question is, I am not passing message variable to that function. How it's working fine. "let" are works with blocks only right?. I am using Scratch js add on for this tutorial.

[athulliapaulose]

let displayColors = function(){

console.log(message)
for(let i in arguments){
console.log(arguments[i]);
}
}

let message = "List of colors";

displayColors(message, 'Red');
displayColors(message, 'Red', 'Blue');
displayColors(message, 'Red', 'Blue', 'Green');



This gives error
Expected 0 arguments, but got 3.ts(2554)
but still compiles and run but my output is
Red
undefined
Red
Blue
undefined
Red
Blue
Green
undefined

Why the message is coming as undefined
Thanks in advance!