   #PHP Manual Variable Functions doubleval floatval

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                                     empty

   (PHP 3, PHP 4 )
   empty -- Determine whether a variable is empty

Description

   bool empty ( mixed var)

   empty() returns FALSE if var has a non-empty or non-zero value. In
   otherwords, "", 0, "0", NULL, FALSE, array(), var $var;, and objects
   with empty properties, are all considered empty. TRUE is returned if
   var is empty.

   empty() is the opposite of (boolean) var, except that no warning is
   generated when the variable is not set. See converting to boolean for
   more information.

   Example 1. A simple empty() / isset() comparison.
   <?php
   $var = 0;
   // Evaluates to true because $var is empty
   if (empty($var)) {
       echo '$var is either 0, empty, or not set at all';
   }
   // Evaluates as true because $var is set
   if (isset($var)) {
       echo '$var is set even though it is empty';
   }
   ?>

     Note: Because this is a language construct and not a function, it
     cannot be called using variable functions

     Note: empty() only checks variables as anything else will result in
     a parse error. In otherwords, the following will not work:
     empty(addslashes($name)).

   See also isset(), unset(), array_key_exists(), count(), strlen(), and
   the type comparison tables.
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