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Re: Date false

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Stefan Ram wrote:

>   Since the OP apparently had an object, I wondered whether an object
>   can be made falsy somehow. The following did not work:
> 
> if( { valueOf: function (){ return false; }})document.writeln( 'a' );
> 
>   . »Not work« means that it wrote »a«.
> 
>   In fact, »9.2 ToBoolean« says that any object always is converted
>   to true,

No, it says that any *value of the Object type* is converted to “true”.

>   so I really do not understand how in the OP's
> 
> if( d )do_something();
> 
>   it is possible that »do_something();« is not executed, when d is
>   either a string (that is not equal to »""«) or an object.

As the “typeof” operation (§11.4.3) resulted in "date" – neither "object" 
nor "function" – we must assume that the value is of an additional type for 
which the “ToBoolean” algorithm has been augmented in the used 
implementation, according to §2 “Conformance”.

-- 
PointedEars
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Thread

Date false Andrew Poulos <ap_prog@hotmail.com> - 2014-05-09 14:18 +1000
  Re: Date false Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-05-09 10:46 +0200
  Re: Date false "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-05-09 10:58 +0200
  Re: Date false Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-05-09 11:01 +0200
  Re: Date false Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-05-09 17:27 -0300
    Re: Date false Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-05-09 17:32 -0300
    Re: Date false Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-05-10 10:36 +0200
  Re: Date false Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-05-09 18:05 -0300

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