Can I use catch(e if e instanceof SyntaxError) in Node.js's javascript?

Question

I read about try catch(e if e instanceof ...) blocks on MDN, however, upon trying it in Node.js, I get a SyntaxError: Unexpected token if.

If this doesn't work, is there another way to catch specific exceptions, instead of everything that might occur?

not sure, but you could catch it and rethrow it after inspecting it. — goat
– goat, Commented May 7, 2012 at 17:03

Bergi · Accepted Answer · 2013-05-29 16:01:58Z

17

To cite the MDN doc you linked to:

Note: This functionality is not part of the ECMAScript specification.

and

JavaScript 1.5, NES 6.0: Added multiple catch clauses (Netscape extension).

so: No, this won't be possible in Node.js. Yet, of course you can use the following syntax as a workaround:

try {
    try_statements
} catch (e) {
    if (e instanceof ...)
        catch_statements_1
    else if (e instanceof ...)
        catch_statements_2
    else
        throw e;
} [finally {
    finally_statements
}]

edited May 29, 2013 at 16:01

answered May 7, 2012 at 18:15

Bergi

671k162 gold badges1k silver badges1.5k bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

afreeland Over a year ago

Appreciate the MDN citation ... totally missed that part when reading the documentation, works well now.

Ugo Evola Over a year ago

I'm sorry to ask, but does anyone know why this feature is neither standard nor being standardized ? It could be great !

Bergi Over a year ago

@UgoEvola It didn't make it into ES5, and interest since then has waned, probably because it's so easy to workaround with a little boilerplate. The pattern matching proposal explores new ways to do this.

Collectives™ on Stack Overflow

Can I use catch(e if e instanceof SyntaxError) in Node.js's javascript?

1 Answer 1

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related