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Re: What's wrong with this code?

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From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.lang.javascript
Subject Re: What's wrong with this code?
Date Thu, 26 Feb 2015 14:25:22 +0000
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denissavenok@gmail.com writes:

> The function doesn't work as expected. Why?
>     
> var isUndefinedOrNull = function(obj) {
>         return /^(?:undefined|null)$/.test(typeof obj);
> };

If the type of obj is Null, typeof is defined to yield 'object'.

You might (in some very odd implementation) get 'null' from typeof, but
that's only because the result is up to the implementation in some very
specific cases.

-- 
Ben.

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Thread

What's wrong with this code? denissavenok@gmail.com - 2015-02-26 01:18 -0800
  Re: What's wrong with this code? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-02-26 12:17 +0100
  Re: What's wrong with this code? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-02-26 14:25 +0000
    Re: What's wrong with this code? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-02-26 16:04 +0100
      Re: What's wrong with this code? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-02-26 15:37 +0000
        Re: What's wrong with this code? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-02-26 17:09 +0100
  Re: What's wrong with this code? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-02-26 14:09 -0300

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