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Remove list elements while condition is met
JavaScript, Array · Nov 29, 2020
Removes elements in an array until the passed function returns false.
Returns the removed elements.
- Loop through the array, using a
for...ofloop overArray.prototype.entries()until the returned value from the function is falsy. - Return the removed elements, using
Array.prototype.slice(). - The callback function,
fn, accepts a single argument which is the value of the element.
const takeWhile = (arr, fn) => {
for (const [i, val] of arr.entries()) if (!fn(val)) return arr.slice(0, i);
return arr;
};takeWhile([1, 2, 3, 4], n => n < 3); // [1, 2]More like this
Remove list elements from the end while condition is met
JavaScript, Array
Removes elements from the end of an array until the passed function returns
false. Returns the removed elements.Remove list elements from the end until condition is met
JavaScript, Array
Removes elements from the end of an array until the passed function returns
true. Returns the removed elements.Remove list elements until condition is met
JavaScript, Array
Removes elements in an array until the passed function returns
true. Returns the removed elements.