> If they are uninitialized then they are null, 0 or false, depending on
the actual type. 
 
Or NaN, for an uninitialized Number.
 
- Gordon

________________________________

From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On
Behalf Of Peter Hall
Sent: Thursday, October 25, 2007 7:29 PM
To: flexcoders@yahoogroups.com
Subject: Re: [flexcoders] Can't use an undefined conditional anymore?



Just to tie up the loose ends... if a variable has a type annotation
then undefined is an illegal value. Only untyped variables, or variables
typed as *, may be assigned with undefined. If they are uninitialized
then they are null, 0 or false, depending on the actual type. Your code
probably works because the value is actually null, and the == operator
does not differentiate between null and undefined (the === operator does
however make this distinction). 

see:
http://livedocs.adobe.com/flex/201/langref/specialTypes.html#*
<http://livedocs.adobe.com/flex/201/langref/specialTypes.html#*> 
http://livedocs.adobe.com/flex/201/langref/package.html#undefined
<http://livedocs.adobe.com/flex/201/langref/package.html#undefined> 

Peter



On 10/25/07, [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
<[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > wrote: 

        Nice - much more elegant - thanks alot

        
        
        > if(foo) will give you the same result. basically if the
instance is there
        > it'll work else it won't
        >
        > On 10/25/07, [EMAIL PROTECTED] <mailto:tim%40e-smartz.com>  <
[EMAIL PROTECTED] <mailto:tim%40e-smartz.com> > wrote:
        >>
        >> Hi,
        >>
        >> I used to do conditionals based on undefined all the time in
AS 2. For
        >> example I would do a data look up and then cast the results
to a class
        >> called foo. Then I could do a conditional if (foo ==
undefined) // go
        >> and
        >> do whatever as the data ovbiously doesn't exist or has not
been
        >> recieved.
        >> Now in AS3 this method still works but I get a warning that
the class
        >> cannot be undefined and undefined will be type coerced into a
foo class.
        >> As I said it still wors so I'm not too fussed, but it's never
good to
        >> see
        >> warnings!
        >>
        >> Tim
        >>
        >>
        >>
        >
        >
        >
        > --
        > j:pn
        > \\no comment
        >
        
        

        

        


 

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