Finished

Test Name	Status
empty	Pass
no nesting	Pass
flattens a nested array	Pass
flattens array with just integers present	Pass
5 level nesting	Pass
6 level nesting	Pass
undefined values are omitted from the final result	Pass
null values are omitted from the final result	Pass
consecutive null values at the front of the array are omitted from the final result	Pass
consecutive null values in the middle of the array are omitted from the final result	Pass
6 level nested array with null values	Pass
all values in nested array are null	Pass

  * @returns {any[]}
  */
 export const flatten = (arr) => {
+  throw new Error('Remove this line and implement the function');
+  // Edge Case: Input is null or undefined
+  if (arr === null || arr === undefined) {
+    return [];
+  }
+  // Edge Case: Input is not an array
+  if (!Array.isArray(arr)) {
+    return [];
+  }
+  const result = [];
+  for (let i = 0; i < arr.length; i++) {
+    const element = arr[i];
+    // Edge Case: Element is null or undefined - skip these values
+    if (element === null || element === undefined) {
+      continue;
+    }
+    // Edge Case: Element is an array - recursively flatten it
+    if (Array.isArray(element)) {
+      const flattened = flatten(element);
+      result.push(...flattened);
+    } else {
+      // Edge Case: Element is a non-array value - add it to result
+      result.push(element);
+    }
+  }
+  return result;
 };
+// Handled Edge Cases: null/undefined input, non-array input, null/undefined elements, nested arrays, mixed data types

kale