Evaluate postfix after assignment

Typo. I'm worrying about this:

arr[i++]=obj[e]

More so the return =obj[e]

I worry on this:

arr[i++]//this will evaluate first before the value return since the = have a lower  
precedence than ++.

So the index that is assign the object will be the index that contains it's string name.

Here reference for precedence:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Operator_Precedence

> On May 12, 2015, at 3:08 PM, Rick Waldron <waldron.rick at gmail.com> wrote:
> 
> 
> 
>> On Tue, May 12, 2015 at 1:58 PM Emanuel Allen <emanuelallen at hotmail.com> wrote:
>> Is this the same across browsers:
>> var i = 0, arr = 'a','b','c'], e,
>> obj = {a:{name:'a'}, b:{name:'b'},c:{name:'c'}};
>> while ((e=arr[i])&&(arr[i++]=obj[e]));
>> 
>> //output:
>> >arr
>> >[{name:'a'},{name:'b'},{name:'c'}]
> 
> Yes
>  
>> 
>> I'm worrying about the "i++"...
> 
> Worried about what, exactly?
> 
> Your subject says "prefix", but this is the postfix operator.
>  
>> I test it out in node's repl... V8... Should the language it self be the same across browsers in situation like this?
> 
> Yes, absolutely. It's explicitly described in the spec (and has been for a very long time).  
> 
> Rick
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Emanuel Allen schrieb:
> Typo. I'm worrying about this:
>
> arr[i++]=obj[e]
>
> arr[i++]//this will evaluate first before the value return since the = have a lower
> precedence than ++.

Notice that operator precedence has to do with parsing an (otherwise 
ambiguous) expression, not with evaulation order.

So this is parsed to

   (((arr)[((i)++)])=((obj)[(e)]))

and then basically evaluated left-to-right.

  Bergi

Oh wow that seem like a lot of work the interpreter is doing...

Thank you for the explanation guys/gals.

Aim to be a JS MASTER.

> On May 12, 2015, at 6:25 PM, Bergi <a.d.bergi at web.de> wrote:
> 
> Emanuel Allen schrieb:
>> Typo. I'm worrying about this:
>> 
>> arr[i++]=obj[e]
>> 
>> arr[i++]//this will evaluate first before the value return since the = have a lower
>> precedence than ++.
> 
> Notice that operator precedence has to do with parsing an (otherwise ambiguous) expression, not with evaulation order.
> 
> So this is parsed to
> 
>  (((arr)[((i)++)])=((obj)[(e)]))
> 
> and then basically evaluated left-to-right.
> 
> Bergi