Implement a function compact(array) that creates an array with all falsey values removed. The values false, null, 0, '', undefined, and NaN are falsey (you should know this by heart!).

Arguments

1. array (Array): The array to compact.

Returns

(Array): Returns the new array of filtered values.

Examples

compact([0, 1, false, 2, '', 3,null]); // => [1, 2, 3]
compact(['hello', 123, [], {}]); // => ['hello', 123, [], {}]

Resources

• Lodash _.compact

Editorial

Solution

/**
 * @param {Array} array: The array to compact.
 * @return {Array} Returns the new array of filtered values.
 */
export default function compact(array) {
  const result = [];

  for (let i = 0; i < array.length; i++) {
    const value = array[i];

    // Skip falsey values
    if (value) {
      result.push(value);
    }
  }

  return result;
}

Here's a simpler solution that leverages Array.prototype.filter.

Open files in workspace

/**
 * @param {Array} array: The array to compact.
 * @return {Array} Returns the new array of filtered values.
 */
exportdefaultfunction compact(array) {
return array.filter(Boolean);
}

Edge cases