Is it possible that there are no consequences to alterations made in .forEach()?

Question

Is it possible that there are no consequences to alterations made in .forEach()?

Just a heads up, I'm currently coding in Codecademy which might be causing some quirks.

I've been working on a task to remove all punctuation from an array called dupBW and convert everything to lowercase.

Interestingly, my code appears to work fine within the forEach loop as indicated by console.log. However, when I check dupBW at the end, it seems unchanged.

Any assistance would be greatly appreciated.

  dupBW.forEach(dupWord => {
    if(puncArray.includes(dupWord[dupWord.length-1])) {
      dupWord = dupWord.slice(0, dupWord.length-1);
      dupWord = dupWord.toLowerCase();
      console.log(dupWord);
    }
  });
  
  console.log(dupBW.join(' '));

javascript arrays foreach

Answer 1

Answer №1

To make it work, replace forEach with map and return dupWord at the end by assigning the array to the newly returned one. Using Array.prototype.map will create a new array with the return values of the callbacks.

modifiedWords = modifiedWords.map(word => {
    if(punctuationMarks.includes(word[word.length-1])) {
      word = word.slice(0, word.length-1);
      word = word.toLowerCase();
      console.log(word);
    }
    return word;
});

console.log(modifiedWords.join(' '));

Answer 2

To make it work, replace forEach with map and return dupWord at the end by assigning the array to the newly returned one. Using Array.prototype.map will create a new array with the return values of the callbacks.

modifiedWords = modifiedWords.map(word => {
    if(punctuationMarks.includes(word[word.length-1])) {
      word = word.slice(0, word.length-1);
      word = word.toLowerCase();
      console.log(word);
    }
    return word;
});

console.log(modifiedWords.join(' '));

Answer 3

Answer №2

When referring to the documentation for .forEach(), it is noted that forEach does not alter the array it operates on. In order to modify the array, alternatives such as a regular for loop, map, or reduce can be used.

An example of this in action is shown below:

let newArr = myArr.map(item => {
    if(someCondition) {
      item = performActionOnItem(item);
      console.log(item);
    }
    return item;
  });
  
  console.log(newArr.join(' '));

Answer 4

When referring to the documentation for .forEach(), it is noted that forEach does not alter the array it operates on. In order to modify the array, alternatives such as a regular for loop, map, or reduce can be used.

An example of this in action is shown below:

let newArr = myArr.map(item => {
    if(someCondition) {
      item = performActionOnItem(item);
      console.log(item);
    }
    return item;
  });
  
  console.log(newArr.join(' '));

Is it possible that there are no consequences to alterations made in .forEach()?

Answer №1

Answer №2

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