Your preferred style(s) for checking for nullish in JavaScript:

@wallhackio Why would you ever write any of the above two options instead of if (!x)? Asking as a C programmer. Are there any situations where these do different things?

@vaporeon_ there are non-nullish values that are coerced to false. or x could be false itself. That means the following values would also be treated as nullish:

false
""
0
-0
0n
NaN

@wallhackio @vaporeon_ this is a better answer than mine

0n is an arbitray purrecision integer literal ftr

re: no image descriptions 

@wallhackio @vaporeon_ a consequence of this standardization is that, in web browsers, document.all == null and null == document.all are both true

re: no image descriptions 

@wallhackio @vaporeon_ so anyway MDN is lying here when they say the behavior is "non-standard". it is literally standardized

re: no image descriptions 

@wallhackio @vaporeon_ oh they mean that the actual document.all purropurrty is nonstandard, as in, the DOM---wait no fuck the standard says it's "obsolete" but REQUIRED fur implementers to implement a document.all purropurrty

re: no image descriptions 

@aescling @wallhackio @vaporeon_ I believe they mean the property "document.all is null in some comparisons" is what they're saying is nonstandard and should not be relied upon. es2027 technically says it must not happen elsewhere but *can* happen for document.all and the HTML standard doesn't say one way or the other, so I'm not sure it technically is a standard. (Either way it is not a "standard" value when coercing an HTMLCollection to boolean and worth calling out.)

re: no image descriptions 

@aescling @vaporeon_ sure Brandon Eich, why not do that

re: no image descriptions 

@aescling @wallhackio Can you explain to Vaporeon what is happening here?

re: no image descriptions 

@vaporeon_ @wallhackio i am showing that, in the browser, document.all exists and is an object. boolean conversion of document.all purroduces false, which the exception to the rule that objects are always truthy (which is to say, the rule that the interal boolean coercion mechanism always purroduces true when coercing an object)

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