JavaScript: Takes a predicate and array, like Array.filter(), but only keeps x if pred(x) returns false
JavaScript: Exercise-155 with Solution
Write a JavaScript program that takes a predicate and an array, like Array.filter(), but only keeps x if pred(x) returns false.
Filters an array's values based on a predicate function, returning only values for which the predicate function returns false.
- Use Array.prototype.filter() in combination with the predicate function, pred, to return only the values for which it returns false.
Sample Solution:
JavaScript Code:
//#Source https://bit.ly/2neWfJ2
const reject = (pred, array) => array.filter((...args) => !pred(...args));
console.log(reject(x => x % 2 === 0, [1, 2, 3, 4, 5]));
console.log(reject(word => word.length > 4, ['Apple', 'Pear', 'Kiwi', 'Banana']));
Sample Output:
[1,3,5] ["Pear","Kiwi"]
Pictorial Presentation:
Flowchart:

Live Demo:
See the Pen javascript-basic-exercise-155-1 by w3resource (@w3resource) on CodePen.
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Previous: Write a JavaScript program to create an object composed of the properties the given function returns falsey for. The function is invoked with two arguments: (value, key).
Next: Write a JavaScript program to apply a function against an accumulator and each element in the array (from left to right), returning an array of successively reduced values.
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