Code examples for mrbalihai.github.io/2016/01/15/making-the-most-of-the-javascript-language.html

browserify-babelify.sh

npm install -g browserify babelify
browserify -t babelify es6code.js > es5code.js

closure-example.js

var outer = function () {
  var a = 1; // variables declared outside of the 'inner' function declaration
  var b = 2;

  return function inner() {
    return a; // return 'a' that was defined in the outer function.
    // return b; // We could also access 'b' if we felt like it.
  };
};

var inner = outer(); // the outer function returns the inner function
inner(); // => 1 // the inner functions still remembers that 'a' was defined as '1' from the outer function

es6-example.js

const myArray = [1, 2, 3, 4, 5, 6]
const add = (a, b) => a + b;
const getTotal = (arr) => arr.reduce(add, 0);

getTotal(myArray); // => 21

first-class.js

var myArray = [1, 2, 3, 4, 5, 6]

var add = function (a, b) {
  return a + b;
};

var getTotal = function (arr) {
  return arr.reduce(add, 0);
};
getTotal(myArray); // => 21

scope-example.js

var foo = function () {
  var a = 2,
      b = 4;

  var bar = function () {
    var b = 9,
        c = 14;
    // Here: a is 2, b is 9 and c is 14

    a = a + b + c;
    // Here: a is 25, b is still 9 and c is still 14
  };

  // Here: a is 2, b is 4 and c is undefined

  bar();
  // Now: a is 25, b is still 4 and c is still undefined
};