JavaScript: Get a customized coalesce function that returns the first argument that returns true from the provided argument validation function

JavaScript fundamental (ES6 Syntax): Exercise-42 with Solution

Write a JavaScript program to get a customized coalesce function that returns the first argument that returns true from the provided argument validation function.

• Use Array.prototype.find() to return the first argument that returns true from the provided argument validation function, valid.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const coalesceFactory = valid => (...args) => args.find(valid);
const customCoalesce = coalesceFactory(_ => ![null, undefined, '', NaN].includes(_));
console.log(customCoalesce(undefined, null, NaN, '', 'Waldo'));

Sample Output:

Waldo

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-42 by w3resource (@w3resource) on CodePen.

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