Javascript_course/06-booleans.html at main · CesarDevtools/Javascript_course · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Booleans</title>
</head>
<body>


    <script>
/*
        //the only booleans values
        true
        false

        console.log(3 > 5 - 5);

        console.log(5 === '5.00');


        //if statements

        if (false){
            console.log("hello");
        }

        else {
            console.log("else")
        };

        // See if someone is old enough to drive


        const age = 15;

        if (age >= 16) {
            console.log('you can drive')
        }

        else if (age >= 14) {
            console.log('almost there')
        }

        else {
            console.log('you  cant drive')
        };


        //AND operator

        console.log(true && true);

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


        //OR operator

        console.log(true || false);

        //NOT operator

        console.log(!true);


// truthy and falsy values.
// Falsy values (false,  0, '', undefined, null, NaN)  any other value is truthy


if (5) {
    console.log('truthy')
}


//
const cartQuantity = 1;
const cartQuantity2 = 0;
// since the cartQuantity is not 0 it'll behave like true truthy. if it was equal to 0 it'd behave like falsy

//so we using this as a shortcut to not type: cartQuantity > 0

if (cartQuantity) {
    console.log('cart has products')
};

if (cartQuantity2) {
    console.log('cart has products')
};
*/

//shortcuts for  if-statements

//ternary operator ?
 const result = 0 ? 'truthy' : 'falsy'
 console.log(result)


 //guard operator &&

//when first value is falsy, the operator will guard the next result and give the first one insteads
 false && console.log('hello')

 const message = 5 && 'hello'
 console.log(message)

// Default operator (similar to guard but uses or " || ")
//the difference here is that when the first value is falsy, it will give the second one intead
let currency = 'EUR' || 'USD';
console.log (currency)

let currency2 = undefined ||'USD'
console.log(currency2)


//Shortcuts are not mandatory to use but they will save us some code
</script>
</body>
</html>