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Bug #5760 isset() on a non existant variable returns the null string instead of false.
Submitted: 2000-07-24 16:30 UTC Modified: 2000-07-24 16:39 UTC
From: daniele at libertyline dot com Assigned:
Status: Closed Package: Misbehaving function
PHP Version: 4.0.1pl2 OS: linux
Private report: No CVE-ID: None
View Developer Edit
 [2000-07-24 16:30 UTC] daniele at libertyline dot com 
The line

	echo isset($non_existant_variable)

returns 0 on php3 and nothing on php4.

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 [2000-07-24 16:39 UTC] derick@php.net 
This is normal behavior for PHP4.

The display of a false value results in "" (the empty string).
The display of a true value results in 0.
 
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