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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.lang.javascript
Subject: Re: check for obj nested prop
Date: Sat, 09 May 2020 03:09:00 +0100
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Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:

> Ben Bacarisse wrote:
>
>> Andrew Poulos <ap_prog@hotmail.com> writes:
>>> so I end up doing
>>>
>>> if (a && a.b && a.b.c && a.b.c.d)
>> <cut>
>>> Is there a way to get the check value of an object's nested property
>>> without first having to test for all the ascendant properties?
>> 
>>   if (try {obj.a.b.c.d} catch {})
>> 
>> might do what you want.
>
> This is *obviously* syntactically invalid;

Yes, wishful thinking.  You'd need a function call and a return:

  if ( (()=>{ try {return obj.a.b.c.d} catch {} })() ) ...

which makes it rather clumsy.

-- 
Ben.