Re: [PHP-DEV] variable_exists() patch

[walt boring]

Stefan Walk wrote:

On Thu, Aug 14, 2003 at 11:15:51AM -0700, walt boring wrote:
 

I for one would like to see something like variable_exists(), as I am 
very annoyed with
the logic of isset() returning false if the variable exists and has a 
value of null. 
   

[snip] 
 

I for one would much rather do
if ( variable_exists($var) ) {}  versus
if (isset($var) || is_null($var)) {}
   

When do you need to do that? I can't think of many situations where it
would be neccessary to check if a variable really exists.
 

It can happen quite easily.  I always develop with full warnings/errors on.
So if for example a var isn't set for whatever reason,  then trying to 
access the
variable will throw a php Notice.  variable_exists() would prevent that, 
as does isset().
isset() would work for my example below, but it still is a 'broken' 
function in my opinion.

if ($var) {  // <-- you'll get a php notice on this line
 switch ($var) {
   ...
 }
}

versus doing

if (variable_exists($var))  {  //no php notices here
 switch($var) {
  ...
 }
}