Refactor Global Variables Out of Functions2

Tell us what’s happening:
As i understand the task says do not change the global variable bookList and I assigned that variable to another inside a function but I am getting (newArr.indexOf is not a function) error

Your code so far


// the global variable
var bookList = ["The Hound of the Baskervilles", "On The Electrodynamics of Moving Bodies", "Philosophiæ Naturalis Principia Mathematica", "Disquisitiones Arithmeticae"];

/* This function should add a book to the list and return the list */
// New parameters should come before the bookName one

// Add your code below this line
function add (bookL,bookName) {
   let newArr=bookL;
  return newArr.push(bookName);
  
  // Add your code above this line
}

/* This function should remove a book from the list and return the list */
// New parameters should come before the bookName one

// Add your code below this line
function remove (bookL,bookName) {
   let newArr=bookL;
  if (newArr.indexOf(bookName) >= 0) {
    
    return newArr.splice(0, 1, bookName);
    
    // Add your code above this line
    }
}

var newBookList = add(bookList, 'A Brief History of Time');
var newerBookList = remove(bookList, 'On The Electrodynamics of Moving Bodies');
var newestBookList = remove(add(bookList, 'A Brief History of Time'), 'On The Electrodynamics of Moving Bodies');

console.log(bookList);

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Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/functional-programming/refactor-global-variables-out-of-functions

I have edited my question

thanks I found my error and i solved it

var bookList = ["The Hound of the Baskervilles", "On The Electrodynamics of Moving Bodies", "Philosophiæ Naturalis Principia Mathematica", "Disquisitiones Arithmeticae"];

/* This function should add a book to the list and return the list */
// New parameters should come before the bookName one

// Add your code below this line
function add (bookL,bookName) {

	 let newArr=[...bookL];
 	  newArr.push(bookName);
 	  return newArr;
  
  // Add your code above this line
}

/* This function should remove a book from the list and return the list */
// New parameters should come before the bookName one

// Add your code below this line
function remove (bookL,bookName) {
	console.log(bookL);
	let newArr=[...bookL];

  if (newArr.indexOf(bookName) >= 0) {
    newArr.splice(newArr.indexOf(bookName), 1)
    return newArr;
    
    // Add your code above this line
    }
}

var newBookList = add(bookList, 'A Brief History of Time');
var newerBookList = remove(bookList, 'On The Electrodynamics of Moving Bodies');
var newestBookList = remove(add(bookList, 'A Brief History of Time'), 'On The Electrodynamics of Moving Bodies');

console.log(bookList);

Thanks one more time, I have almost forgotten how to copy an array with using spread and how to use splice, I reviewed them.

1 Like

i spent over 2 hours on this bullshit question. i was technically right but some tiny syntax was wrong for some fucking reason man im raging.