JavaScript: Check if the predicate is truthy on all elements of a collection

JavaScript fundamental (ES6 Syntax): Exercise-116 with Solution

Truthy Predicate Check on Collection

Write a JavaScript program to check if the predicate (second argument) is truthy on all elements of a collection (first argument).

• Use Array.prototype.every() to check if each passed object has the specified property and if it returns a truthy value.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2

// Define the 'truthCheckCollection' function.
const truthCheckCollection = (collection, pre) => collection.every(obj => obj[pre]);

// Example usage: Checking if all objects in a collection have a truthy value for a given property.
console.log(truthCheckCollection([{ user: 'Tinky-Winky', sex: 'male' }, { user: 'Dipsy', sex: 'male' }], 'sex'));
// Output: true

Output:

true

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-116-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that checks if all elements in a collection return true when passed to a provided predicate function.
• Write a JavaScript function that iterates over an array and returns true only if the predicate is truthy for every element.
• Write a JavaScript program that uses Array.every() to verify that every item in a collection satisfies a given test.

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