[PHP-DOC] cvs: phpdoc /en/functions var.xml From: Damien Seguy (dams <email protected>)
Date: 05/21/01

dams Mon May 21 04:13:31 2001 EDT

  Modified files:
    /phpdoc/en/functions var.xml
  Log:
  Adding zak's note
  
Index: phpdoc/en/functions/var.xml
diff -u phpdoc/en/functions/var.xml:1.49 phpdoc/en/functions/var.xml:1.50
--- phpdoc/en/functions/var.xml:1.49 Sat May 19 13:41:43 2001
+++ phpdoc/en/functions/var.xml Mon May 21 04:13:29 2001
@@ -810,13 +810,18 @@
     </simpara>
     <para>
      If a variable has been unset with <function>unset</function>,
- it will no longer be <function>isset</function>.
+ it will no longer be <function>isset</function>. <function>isset</function>
+ will return <literal>FALSE</literal> if testing a variable that has been
+ set to <literal>NULL</literal>. Also note that a null byte (<literal>"\0"</literal>)
+ is not equivalent to the PHP <literal>NULL</literal> constant.
      <informalexample>
       <programlisting role="php">
 $a = "test";
-echo isset ($a); // true
+echo isset ($a); // TRUE
 unset ($a);
-echo isset ($a); // false
+echo isset ($a); // FALSE
+$foo = NULL;
+print isset ($foo); // FALSE
       </programlisting>
      </informalexample>
     </para>