Coding styles in JS

codingStyles.js

/*
Case study
Write a function that, when given an object returns the value of a specific property of that object.

Exercise
Create an object with two numeric properties (x=42 and y=666) and log just the x property to the console.
*/

// Procedural style
{
  function getPropertyX(obj) {
    return obj.x;
  }

  const testObj = { x: 43, y: 666 };
  console.log('Procedural', getPropertyX(testObj));

  // or taking the instructions literally.
  function logPropertyX(obj) {
    console.log('Procedural', obj.x);
  }
}

// OOP style (use a method because everything is an object/class!)
{
  class classZ {
    #x;
    #y;

    constructor(x, y) {
      this.#x = x;
      this.#y = y;
    }

    get x() {
      return this.#x;
    }
  }

  const testObj = new classZ(42, 666);
  console.log('OOP', testObj.x);
}

// or, literally, add method log
{
  class classZ {
    #x;
    #y;

    constructor(x, y) {
      this.#x = x;
      this.#y = y;
    }

    log() {
      console.log('OOP', this.#x);
    }
  }

  // and call:
  const testObj = new classZ(42, 666);
  testObj.log();
}

// Functional style
{
  const getProperty = (propName) => (obj) => obj[propName];

  const testObj = { x: 42, y: 666 };
  console.log('Functional', getProperty(`x`)(testObj));

  // or
  const getX = getProperty(`x`);
  console.log('Functional', getX(testObj));
}