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Comment by dragonwriter | Hacker News Reader

But, why would you want the declaration in the try when the scope of the variable is broader? It's true that var let's you do that, but it seems to me that's strictly a misleading thing.

Sure, you’ll often need to split declaration from assignment with let in that case, but that's not a bad thing, IME.

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    try {
        const { attribute1, attribute2 } = getObject()
    } catch () {}
    attribute1 // undefined

How would you solve that?

With let outside the try, because that's the intended scope. Insofar as there is a problem I see with that, it's that you can't separate declaration of a single-assignment value (const) from the one allowed assignment, because the ideal solution would be const declared outside the try with the assignment inside.

OTOH var declared inside is a bad solution because it's both misleading as to scope and using a freely-assignable variable for something that's logically single-assignment. Let outside has only one of those problems.

Exactly, I'm just pointing out the limitations of `let/const`

I usually solve that case with

    let attribute1, attribute2;
    try {
         const object = getObject()
         attribute1 = object.attribute1
         attribute2 = object.attribute2
    } catch () {}

But I'm just not satisfied with it, too many statements. And it gets really messy with many attributes

How about this:

    let attribute1, attribute2;
    try  {
     ({attribute1, attribute2} = getObject())
    } catch (e) {}

wow, didn't know that!

So parenthesis are the trick, thanks!

No problem!

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