How Can I Efficiently Select Random Array Items Without Repeats?

How to Efficiently Randomly Select Array Item Without Repeats

Your code creates an array of recent choices to prevent repetition, and calls a recursive function named chooseName() when a selected item is in the recent choices. This approach ensures uniqueness but may lead to an infinite loop if the array size is limited.

Is It a Recursive Function?

Yes, chooseName() calls itself to find a unique selection. Recursion enables the function to iterate through array items until it finds one that is not in the recent choices.

Improving Efficiency

To avoid infinite looping, consider an alternative approach suggested in the answer:

<code class="javascript">function randomNoRepeats(array) {
  var copy = array.slice(0);
  return function() {
    if (copy.length < 1) { copy = array.slice(0); }
    var index = Math.floor(Math.random() * copy.length);
    var item = copy[index];
    copy.splice(index, 1);
    return item;
  };
}</code>

This function generates a copy of the original array and randomly chooses an item from it. Once all items are used, it creates a new copy of the original array, ensuring unique selections even when the array is exhausted.

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