Removing Array Elements Based on a Condition
To remove elements in an array based on a condition, open the Terminal/SSH and type node
.
The takeWhile
function removes elements in an array until the passed function returns false
, and then returns the removed elements.
Here are the steps to use the takeWhile
function:
- Loop through the array using a
for...of
loop over Array.prototype.entries()
.
- Loop until the returned value from the function is falsy.
- Return the removed elements using
Array.prototype.slice()
.
- The
fn
callback function accepts a single argument which is the value of the element.
Use the following code to implement the takeWhile
function:
const takeWhile = (arr, fn) => {
for (const [i, val] of arr.entries()) if (!fn(val)) return arr.slice(0, i);
return arr;
};
Here is an example of using the takeWhile
function to remove elements from an array based on a condition:
takeWhile([1, 2, 3, 4], (n) => n < 3); // [1, 2]