question mark when accessing property javascript
Optional chaining: (?.)
The optional chaining operator (?.) enables you to
read the value of a property located deep within a
chain of connected objects without having to
check that each reference in the chain is valid.
The ?. operator is like the . chaining operator,
except that instead of causing an error if a reference
is nullish (null or undefined), the expression returns
a value of undefined.
When used with function calls,
it returns undefined if the given function does not exist.
Example:
const adventurer = {
name: 'Alice',
cat: {
name: 'Dinah'
}
};
const dogName = adventurer.dog?.name;
console.log(dogName);
// output: undefined
console.log(adventurer.someNonExistentMethod?.());
// output: undefined