| const car1 = { | |
| brand: ‘carBrand1’ | |
| color: ‘red’ | |
| }; | |
| const car2 = undefined; | |
| // it logs a value | |
| console.log(car1.color); | |
| /* | |
| if we do not use null safety mechanism next part of the code will throw Uncaught | |
| ReferenceError: car2 is not defined | |
| */ | |
| console.log(car2.color); | |
| /* | |
| if we use null safety mechanism ?. we will avoid throwing an error and program | |
| will continue to work - it logs undefined | |
| */ | |
| console.log(car2?.color) | |
| /* | |
| like in all other programming languages which does not have null safety mechanism, | |
| we can also write last part of the code in the different, more complicated, way | |
| and add possibility to forget some of the cases which then can cause ReferenceError | |
| */ | |
| console.log(car2 !== undefined ?? car2 !== null ? car2.color : undefined) |