Description:
------------
http://www.php.net/manual/en/language.functions.php#AEN5142

a problem exists in the sample of a manual.
this problem is not checking exist of bar.

The right example:
<?php
function foo() 
{
  if ( !function_exists( "bar")) <== add
  {                              <== add
    function bar() 
    {
     echo "I don't exist until foo() is called.\n";
    }
  }                              <== add
}
?> 


Reproduce code:
---------------
<?php

error_reporting(E_ALL);
ini_set( "display_errors", "on");

function foo()
{
  function bar()
  {
   echo "I don't exist until foo() is called.\n";
  }
}
foo();
bar();
foo();  //  Fatal error: Cannot redeclare bar()

?>


Expected result:
----------------
Fatal error: Cannot redeclare bar() (previously declared in /path/for/script/foo.php:10) in /path/for/script/foo.php on line 8


Actual result:
--------------
I don't exist until foo() is called.
I don't exist until foo() is called.