Why does Javascript cast null to string at variable assignment? -

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• using variable “name” doesn't work js object 3 answers

in firefox 45 on osx, when fetch item localstorage key not exist, function call returns null. tested in console.

if instead assign call result variable, , print value in console, "null", i.e. string.

why variable assignment of not defined variable cast call result string?

used code (in console):

localstorage.getitem("non-existing-key"); // returns null  var x = localstorage.getitem("non-existing-key"); x // returns "null" 

edit: both versions seem behave correctly on chrome 50.0.2661.86 on osx (both return null)

edit2: mistake. used variable name in tests (specifically: var name). now, if let console return value of variable name, returns window.name, property of window of type string, defaulting "null". so, it's not assignment causes cast, instead got string property defined window.

i made mistake. specific code used following:

var name = localstorage.getitem("non-existing-key"); name 

now, getitem return null , not string. happens letting console print value of name in fact window.name (see window.name on mdn), default "null" (a string).