JavaScript: Remove elements in an array until the passed function returns true

JavaScript fundamental (ES6 Syntax): Exercise-241 with Solution

Remove Elements Until Condition

Write a JavaScript program to remove elements from an array until the passed function returns true. Returns the remaining elements in the array.

• Loop through the array, using Array.prototype.slice() to drop the first element of the array until the value returned from func is true.
• Return the remaining elements.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
// Define a function 'dropWhile' to remove elements from the beginning of an array until a condition is met
const dropWhile = (arr, func) => {
  // Iterate over the array while its length is greater than 0 and the condition for the first element fails
  while (arr.length > 0 && !func(arr[0])) 
    // Remove the first element from the array
    arr = arr.slice(1);
  // Return the modified array
  return arr;
};

// Test the 'dropWhile' function with an array and a condition function
console.log(dropWhile([1, 2, 3, 4], n => n >= 3)); // Output: [3, 4]

Output:

[3,4]

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-241-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that removes elements from the start of an array until a provided condition is met and returns the remaining array.
• Write a JavaScript function that uses a while loop to shift elements off an array until a predicate returns true.
• Write a JavaScript program that processes an array and stops removing items once an element satisfies a test.
• Write a JavaScript function that returns the array after all initial elements failing a condition are removed.

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