Difference between undefined and null in JS 1.2 and JS 1.4

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September 13th, 2000, 06:21 AM

MeijdenB

Contributing User

Join Date: May 2000

Location: Alkmaar, The Netherlands

Posts: 123

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Reputation Power: 9

Hi all,

I don't get it anymore. I've been looking at references and specs for a day or 2 now.

I would like to fill the following table with the return values for both JS 1.2 and JS 1.4, because there seems to be a difference.

<BLOCKQUOTE><font size="1" face="Verdana,Arial,Helvetica">code:</font><HR><pre>
local global

not declared not allowed in 1.4 undefined in 1.4
not known in 1.2 not known in 1.2

declared/ undefined in 1.4 undefined in 1.4
no value not known in 1.2 not known in 1.2

declared/ value value
value
[/code]

It could be that all the unknowns are returning null. And that will cause some major differences in serverside javascript applications that we've developed.

Can anybody fill the blank spots for me?

Thanx
Bas
b.vandermeijden@pecoma.nl

[This message has been edited by MeijdenB (edited September 13, 2000).]

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