function scope javascript code example

Example 1: javascript define global variable

window.myGlobalVariable = "I am totally a global Var"; //define a global variable
var myOtherGlobalVariable="I too am global as long as I'm outside a function";

Example 2: closure in javascript

function makeFunc() {
  var name = 'Mozilla';
  function displayName() {
    alert(name);
  }
  return displayName;
}

var myFunc = makeFunc();
myFunc();

Example 3: global scope js

const color = 'blue'

const returnSkyColor = () => {
  return color; // blue 
};

console.log(returnSkyColor()); // blue

Example 4: closure in javascript

var counter = (function() {
  var privateCounter = 0;
  function changeBy(val) {
    privateCounter += val;
  }
  return {
    increment: function() {
      changeBy(1);
    },
    decrement: function() {
      changeBy(-1);
    },
    value: function() {
      return privateCounter;
    }
  };
})();

console.log(counter.value()); // logs 0
counter.increment();
counter.increment();
console.log(counter.value()); // logs 2
counter.decrement();
console.log(counter.value()); // logs 1

Example 5: scope in js

// the scope is by default global
var name = 'Hammad';