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Tolerim
18 hours ago

How can I remove only one element from a JavaScript array that has duplicates?

The given post displays a request to remove a variable number of objects from an array based on their specific id. The array of objects may not always be sorted by id. A vanilla JavaScript solution is required, avoiding the use of libraries and preferably without splice. While arr.filter(({id}) => id !== 1) works, it removes all instances of id 1. An array of objects like the original must remain and only the objects that meet the specified criteria should be removed.
Answers(1)
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Tolerim
18 hours ago
Verified Answer
One possible solution to remove a variable amount of objects with a specific id from an array of objects using vanilla JavaScript is to use the Array.filter() method along with a counter. You can loop through the array and count the number of objects that have the specified id, and then use Array.filter() to create a new array without those objects. Here's an example implementation: 
function removeById(arr, id, removeCount) {
  let count = 0;
  return arr.filter((obj) => {
    if (obj.id === id && count < removeCount) {
      count++;
      return false;
    }
    return true;
  });
}

// Example usage:
const arr = [
  { id: 1 },
  { id: 1 },
  { id: 2 },
  { id: 2 },
  { id: 3 },
];

const newArr = removeById(arr, 1, 1); // remove 1 object with id 1
console.log(newArr);
// Output: [{ id: 1 }, { id: 2 }, { id: 2 }, { id: 3 }];
In this example, the removeById() function takes three arguments: the array arr, the id to remove id, and the number of objects to remove removeCount. Inside the function, we declare a counter variable count initialized to 0. We then use Array.filter() to create a new array by iterating over each object in arr and checking whether its id matches the given id and whether we have removed less than removeCount objects with that id so far. If both conditions are met, we increment count and return false to exclude that object from the new array. Otherwise, we return true to include the object in the new array. Finally, we return the new array. Note that this implementation assumes that the order of the objects in the array does not matter, and that you want to remove the first removeCount objects with the specified id. If you need to remove objects starting from the end of the array or based on a different criteria, you may need to modify the implementation accordingly.
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