JavaScript: Get the first non-null / undefined argument

JavaScript fundamental (ES6 Syntax): Exercise-64 with Solution

Write a JavaScript program to get the first non-null / undefined argument.

  • Use Array.prototype.find() and Array.prototype.includes() to find the first value that is not equal to undefined or null.

Sample Solution:

JavaScript Code:

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


flowchart: Get the first non-null / undefined argument

Live Demo:

See the Pen javascript-basic-exercise-64-1 by w3resource (@w3resource) on CodePen.

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