Question 293385 in Javascript Question posted in
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javascript new and this keyword

I have been given a task at my internship , I have to create math operations like plus(), minus() etc. using this and new keywords.
example:- one().plus().two().equalTo() , given line of code must return 3.

I tried creating functions which returns values.
function one(){ return 1; }.
But I am not able to figureout how plus() and equalto() will work.

Tags:

2

Answers


  1. 0

    Sorry I edited this answer . I have misunderstood the question . I think this is what you are looking for right ? So for starter you can do something like this

    function NumberWrapper(value) {
  this.value = value || 0;
}

NumberWrapper.prototype.plus = function (num) {
  this.value += num;
  return this;
};

NumberWrapper.prototype.equalTo = function () {
  return this.value;
};

function one() {
  return new NumberWrapper(1);
}

function two() {
  return new NumberWrapper(2);
}

// Usage example
const result = one().plus().two().equalTo();

console.log(result); // Output: 3

    to make it more dynamic you can use for loop and create a wrapper of those number

    for e.g 100’s of them

    
function createNumberWrapper(value) {
  return {
    plus: function (num) {
      value += num;
      return this;
    },
    equalTo: function () {
      return value;
    }
  };
}

for (let i = 1; i <= 100; i++) {
  //
}
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  2. 0

    Here’s a solution using function chaining:

    function one() {
  const fn = this._fn;
  if (!fn)
    this._fn = () => 1;
  else
    this._fn = () => fn(1);

  return this;
}

function two() {
  const fn = this._fn;
  if (!fn)
    this._fn = () => 2;
  else
    this._fn = () => fn(2);

  return this;
}

function plus() {
  const fn = this._fn;
  if (!fn)
    this._fn = n => n;
  else
    this._fn = n => fn() + n;

  return this;
}

function equalTo() {
  const fn = this._fn;
  if (fn) {
    delete this._fn;
    return fn();
  }
  return 0;
}


console.log(one().plus().two().equalTo());                // 3
console.log(one().plus().two().plus().two().equalTo());   // 5
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