I have the following code from a project:
setTweetLibrary((curr) => {
if (!curr[0] || (curr[0] && curr[0].id !== saved_tweets[0].id)) {
console.log("update");
return saved_tweets;
} else {
console.log("not update");
return curr;
}
});
I would like to convert this to a ternary operator with a question mark ("?") to make it neater, but I can't figure out how. Can anyone advise? Thank you!
I think I'm just really confused on how the syntax of ternary operators with multiple conditions and values
As ternary it would look like this:
setTweetLibrary((curr) => {
return !curr[0] || (curr[0] && curr[0].id !== saved_tweets[0].id)
? saved_tweets
: curr;
});
Note that there is no more place for console.logs. But they seem to be debug anyway.
The ternary operator is not a generic replacement for an if statement, only for choosing between expressions that are going to the same destination.
If we take out the logging, both branches are returning a variable:
if (!curr[0] || (curr[0] && curr[0].id !== saved_tweets[0].id)) {
return saved_tweets;
} else {
return curr;
}
The fact that the condition is a long expression doesn't make any difference, it's still equivalent to this:
if (some_condition_goes_here) {
return saved_tweets;
} else {
return curr;
}
In that case, you could use a ternary operator to select between the two - move the return to where the if is, and the ? and : before the two values. Then put the whole thing in parentheses to make sure the whole thing is calculated before return:
return (
(some_condition_goes_here)
? saved_tweets
: curr
);
Specifically:
return (
(!curr[0] || (curr[0] && curr[0].id !== saved_tweets[0].id))
? saved_tweets
: curr
);
It might be possible to add the logging in there as well, but it will be much harder to read than just using a normal if statement, so if you want that - or any other logic - just stick with if...else.
This works
return (!curr[0] || (curr[0] && curr[0].id !== saved_tweets[0].id) ? saved_tweets : curr)