try {} without catch {} possible in JavaScript?

I have a number of functions which either return something or throw an error. In a main function, I call each of these, and would like to return the value returned by each function, or go on to the second function if the first functions throws an error.

So basically what I currently have is:

function testAll() {
    try { return func1(); } catch(e) {}
    try { return func2(); } catch(e) {} // If func1 throws error, try func2
    try { return func3(); } catch(e) {} // If func2 throws error, try func3
}

But actually I'd like to only try to return it (i.e. if it doesn't throw an error). I do not need the catch block. However, code like try {} fails because it is missing an (unused) catch {} block.

I put an example on jsFiddle.

So, is there any way to have those catch blocks removed whilst achieving the same effect?

A try without a catch clause sends its error to the next higher catch, or the window, if there is no catch defined within that try.

If you do not have a catch, a try expression requires a finally clause.

try {
    // whatever;
} finally {
    // always runs
}

It's possible to have an empty catch block, without an error variable, starting with ES2019. This is called optional catch binding and was implemented in V8 v6.6, released in June 2018. The feature has been available since Node 10, Chrome 66, Firefox 58, Opera 53 and Safari 11.1.

The syntax is shown below:

try {
  throw new Error("This won't show anything");
} catch { };

You still need a catch block, but it can be empty and you don't need to pass any variable. If you don't want a catch block at all, you can use the try/finally, but note that it won't swallow errors as an empty catch does.

try {
  throw new Error("This WILL get logged");
} finally {
  console.log("This syntax does not swallow errors");
}

Nope, catch (or finally) is try's friend and always there as part of try/catch.

However, it is perfectly valid to have them empty, like in your example.

In the comments in your example code (If func1 throws error, try func2), it would seem that what you really want to do is call the next function inside of the catch block of the previous.

I wouldn't recommend try-finally without the catch, because if both the try block and finally block throw errors, the error thrown in the finally clause gets bubbled up and the try block's error is ignored, in my own test:

try {
  console.log('about to error, guys!');
  throw new Error('eat me!');
} finally {
  console.log ('finally, who cares');
  throw new Error('finally error');
}

Result:

>     about to error, guys!
>     finally, who cares
>     .../error.js:9
>         throw new Error('finally error');
>         ^
>     
>     Error: finally error

No, it is not possible to have try block without catch (or finally). As a workaround, I believe you might want to define a helper function such as this:

function tryIt(fn, ...args) {
    try {
        return fn(...args);
    } catch {}
}

and use it like:

tryIt(function1, /* args if any */);
tryIt(function2, /* args if any */);

try {} without catch {} possible in JavaScript?

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