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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