JavaScript: Return true if the provided predicate function returns true for at least one element in a collection, false otherwise

JavaScript fundamental (ES6 Syntax): Exercise-255 with Solution

Predicate True for Any

Write a JavaScript program that returns true if the provided predicate function returns true for at least one element in a collection, false otherwise.

• Use Array.prototype.some() to test if any elements in the collection return true based on fn.
• Omit the second argument, fn, to use Boolean as a default.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
// Define a function 'any' that checks if any element in the array satisfies the provided condition
const any = (arr, fn = Boolean) => arr.some(fn);

// Test the 'any' function with different arrays and conditions
console.log(any([0, 1, 2, 0], x => x >= 2)); // true (at least one element is greater than or equal to 2)
console.log(any([0, 0, 1, 0])); // true (at least one element is truthy)

Output:

true
true

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-255-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that returns true if a provided predicate function returns true for at least one element in a collection.
• Write a JavaScript function that iterates over an array and uses Array.some() to test if any element passes a test.
• Write a JavaScript program that checks a list of values with a predicate and stops at the first true result.
• Write a JavaScript function that takes a predicate and a collection and returns a boolean indicating if any element satisfies the condition.

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