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javascripttry-catch

Appropriate inline try catch

In Javascript (or for the most part, ECMAscript in general), which is the most appropriate way to write this?

try { ajax.abort() } catch(e) { console.error (e) }

or

try { ajax.abort(); } catch(e) { console.error (e); }

It seems like semi-colons are unneeded for this situation but at the same time I normally write this on 5 lines instead of one in which case I used semicolons for their standard programmatic purpose (eol).

Both work, and I'm sure both will validate, so which is semantically correct?

Solution

  • They're semantically identical, and they're both syntactically correct, because of Automatic Semicolon Insertion.

    This part is opinion:

    I recommend always writing the necessary semicolons explicitly and never relying on ASI. But even if you do that, ASI can bite you. The classic example is:

    function foo() {
    return
        "testing";
}

    If you call foo, the return value will be undefined, not "testing", because ASI kicks in and adds a ; after the return. Ouch.