isEmpty function in Javascript (like 'empty' in PHP)

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Mon Jul 10 2023 16:44:14 GMT+0000 (Coordinated Universal Time)

function isEmpty(value) {
  if (value === undefined) {
    return true;
  }

  if (value === null) {
    return true;
  }

  if (typeof value === 'string' && /^[\s\u00A0]*$/.test(value)) {
    return true;
  }

  if (Array.isArray(value) && value.length === 0) {
    return true;
  }

  if (typeof value === 'object' && Object.keys(value).length === 0) {
    return true;
  }

  if (typeof value === 'number' && isNaN(value)) {
    return true;
  }

  if (value instanceof Date && isNaN(value.getTime())) {
    return true;
  }

  if (typeof value === 'boolean' && !value) {
    return true;
  }

  if (typeof value === 'function') {
    return true;
  }

  // Treat any other object as non-empty
  if (typeof value === 'object') {
    return false;
  }

  return false;
}

// Usage
var moment = require('moment');

var variable1;
console.log(isEmpty(variable1)); // true

var variable2 = null;
console.log(isEmpty(variable2)); // true

var variable3 = 'Hello';
console.log(isEmpty(variable3)); // false

var variable4 = 0;
console.log(isEmpty(variable4)); // true

var variable5 = '0';
console.log(isEmpty(variable5)); // true

var variable6 = '    ';
console.log(isEmpty(variable6)); // true

var variable7 = '\t\t';
console.log(isEmpty(variable7)); // true

var variable8 = '\n';
console.log(isEmpty(variable8)); // true

var variable9 = [];
console.log(isEmpty(variable9)); // true

var variable10 = {};
console.log(isEmpty(variable10)); // true

var variable11 = new Date('Invalid Date');
console.log(isEmpty(variable11)); // true

var variable12 = function() {
  // Function body
};
console.log(isEmpty(variable12)); // true

var variable13 = moment('2023-07-10', 'YYYY-MM-DD');
console.log(isEmpty(variable13)); // false

var variable14 = false;
console.log(isEmpty(variable14)); // true

var variable15 = { foo: 'bar' };
console.log(isEmpty(variable15)); // false

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isEmpty function in Javascript (like 'empty' in PHP)

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