takeWhile

Removes elements in an array until the passed function returns true. Returns the removed elements.

Loop through the array, using a for...of loop over Array.prototype.entries() until the returned value from the function is true. Return the removed elements, using Array.prototype.slice().

typescript

const takeWhile = (arr: any[], func: Predicate) =>
  arr.reduce((acc, el) => (func(el) ? acc : acc.concat(el)), []);

typescript

takeWhile([1, 2, 3, 4], (n) => n >= 3); // [1, 2]