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

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

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 
const truthCheckCollection = (collection, pre) => collection.every(obj => obj[pre]);
console.log(truthCheckCollection([{ user: 'Tinky-Winky', sex: 'male' }, { user: 'Dipsy', sex: 'male' }], 'sex'));

Sample Output:

true

Flowchart:

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

Live Demo:

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


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JavaScript: Tips of the Day

Chunks an array into n smaller arrays

Example:

const tips_chunkIntoN = (arr, n) => {
  const size = Math.ceil(arr.length / n);
  return Array.from({ length: n }, (v, i) =>
    arr.slice(i * size, i * size + size)
  );
}
console.log(tips_chunkIntoN([1, 2, 3, 4, 5, 6, 7,8], 4));

Output:

[[1,2],[3,4],[5,6],[7,8]]