javascript-course/06-booleans.html at main · ajayavula682/javascript-course · GitHub

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<!DOCTYPE html>
<html lang="en">
<head><meta charset="utf-8">

    <title>Booleans</title>

</head>


<body>

       <script>
      /*  console.log(typeof true);
        //console.log(sizeof('true'));

        console.log(3 < 5);
        console.log(3 > 5);
        console.log(3 != 5);
        console.log(3 == 5);

        console.log(5 =='5');// In java script if you compare with '==' then the lag convert both to same data type

        console.log(5 ==='5');
        //this works fine in js
        //following the '!=' is not recommended '!==' is the best way comparing not equals to in the JS
        console.log(5 !='5');
        console.log(5 !=='5'); //comparative operators have lower priority in the operations
        const age =15;
        if(false)
       {
        console.log('hello');
       }
       else{
        console.log('world');//else statement
       }
       if(age >=16)
       {
        console.log('Eligible to drive');

       } else if(age >= 14)
       {
        console.log('Almost there to drive');
       }
       else{
        console.log('Not Eligible to drive');
        console.log('till your age');
       }*/

       /*console.log(true && true); //and operator if two conditions are true the it returns true
       console.log(true && false);// here both are not true so it returns false

       console.log( 0.2 >= 0 && 0.2 < 1/3);

       console.log(Math.random());

       console.log(true  ||false);

       console.log(false || true);// or operator in 2 statements if  atleast on is true then it will return true
       console.log(false || false);

       console.log( !false);
       console.log( !true); */

       if(5)
        {
          console.log('Condition is true');/*truthy value because value inside iff consider as true */

         }


         let n;

         if(NaN){console.log("false value");}
         if(n){console.log("false value");}
         if(false){console.log("false value");}
         if(''){console.log("false value");}
         if(NaN){console.log("false value");}
         console.log(".");// considered as falsy value
         //the following are false ,0 ,'',NaN, undefined,null.excluded the above falsy value remaining values are true.
         //creating truthy and falsy values are to create the shot cut for the execution code.NaN ie; not a number.
         let zero = 0;
if (!zero) {
    console.log("Zero is falsy!"); // Might not be what you intended
}
  const cQuantity=5;

  if(cQuantity> 0) {
    console.log("cart is not empty");
  }
  if(cQuantity)       //works similar way than the above if statements
  {
    console.log("cart is not empty");
  }
  else if (cQuantity <1){
    console.log("cart is empty");
  }
  console.log(!0);

  const a='text'/5;
  console.log(a); //NaN(Not a number)
   let va;
   console.log(va); //undefined


       </script>


</body>
</html>