Search and replace ooo

[stevepatd]

I have a web form that has the user entering their email address.  I've seen some common spelling mistakes and would like to fix those as I process the form data.  It all works except when I'm trying to replace yahooo with yahoo.  It stays as yahooo.  I tried replacing yahooo with yahoo11 and I got yahoo11o.  I tried replacing yahoo with 'thisisatest' and I got 'thisisatesto'.  Is there something special about 'ooo'? 

 

So I tried searching for yahhhh, yahaaa and oooyaha and the program had no problems replacing them with yahoo (when coded for it).

 

I've tried preg_replace and str_replace with the same results.  Any idea what is happening here?

 

Trial 1:

     $email = preg_replace('/yahooo/i','yahoo',$email);

 

Trial 2:
     $email = str_replace('yahooo','thisisatest',$email);
 

[Barand]

I'm guessing there is something else going on

$email = 'fred@yahooo.com';
$email = str_replace('yahooo','yahoo',$email);
echo $email;     //--> fred@yahoo.com