How can I Create a Function for Infinite Calls in JavaScript

Question

I am trying to write a function in JavaScript where there will be an infinite call to greet(). The expected outcome is to have the greetings concatenated with each call.

console.log(greet('hello').greet('world').greet())

the output of the above should give Hello world and there might be infinite greet('string')

My initial implementation looked like this:


let greet = function (a) {
  return  function (a) {
        return function (c){
          return c ? (b + " " + c ) : (a + " " + b);
        }
  }
};

However, the output is not as expected. I am facing some issues in the implementation and would like some help in resolving them. Can someone help me fix this issue? Thank you in advance."

@TrevorDixon. problem statement is to solve ```console.log(greet('hello').greet('world').greet())``` — Praveen Vishnu, Feb 12 '23 at 09:25

score 6 · Answer 1 · answered Feb 12 '23 at 09:33

6

Basically, have a function that returns an object with a function inside which in turn invokes the global function that returns an object... etc

let greet = a => ({
    greet: b => b ? greet(a + ' ' + b) : a
})

console.log(greet('hello').greet('world').greet())

answered Feb 12 '23 at 09:33

gog

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Thanks, @gog. I also found a way. I was trying to do without the arrow function – Praveen Vishnu Feb 12 '23 at 09:51

score 2 · Answer 2 · answered Feb 12 '23 at 10:44

The issue in your code is that you are using the variable b inside the innermost function, but it's not defined in the scope of that function. Also, you are declaring a function with the same name a in the inner function, which shadows the outer a parameter.

Here's a corrected version of the code:

let greet = function (a) {
  let b = a;
  return function (c) {
    if (c) {
      b = b + " " + c;
    }
    return {
      greet: function (d) {
        return greet(b + (d ? " " + d : ""));
      }
    };
  };
};

With this code, you can call greet multiple times and concatenate the greetings with each call. For example:

console.log(greet('hello').greet('world').greet());
// Output: "Hello world"

score 1 · Answer 3 · answered Feb 12 '23 at 09:26

1

You are probably looking for fluent chaining in JavaScript. You can achieve this approach by creating your own custom class and keep returning this:

class Greeter {
  content = '';
  greet(string) {
    this.content += (this.content.length ? ' ' : '') + string;
    return this;
  }
  toString() {
    return this.content;
  }
}

const greeter = new Greeter();
const output = greeter
  .greet('I')
  .greet('can')
  .greet('do')
  .greet('this')
  .greet('forever')
  .toString();
  
console.log(output);

You can check other possibilities by searching it. For example on Stackoverflow are similliar questions.

answered Feb 12 '23 at 09:26

Jax-p

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Thanks for the answers i am trying to end the call by ```.greet()``` – Praveen Vishnu Feb 12 '23 at 09:28
1

Potential issue - mutable shared state. https://jsbin.com/nibizeroju/edit?js,console – VLAZ Feb 12 '23 at 09:39

Praveen Vishnu · Answer 4 · 2023-02-12T09:55:38.957

0

Thank you all for responding to my issue. i also came up through some implementation with traditional function expressions

here is my solution

 let greet = function (a) {
  return {
    greet: function (b) {
      return b ? greet(a + " " + b) : a;
    }
  }
};

edited Feb 12 '23 at 09:55

answered Feb 12 '23 at 09:37

Praveen Vishnu

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How can I Create a Function for Infinite Calls in JavaScript

4 Answers4