Description:
------------
when php receivie the data from external sources, a variables named 'id[[name' will be saved into $_REQUEST['id_[name'];

@see http://php.net/manual/en/language.variables.external.php

Will '[' only be replaced once?

Test script:
---------------
<form method="post">
    <input type="text" name="id[name" value="1">
    <input type="text" name="id[[name" value="a">
    <input type="submit">
</form>

Expected result:
----------------
array ( 
  'id_name' => '1', 
  'id__name' => 'a',
)

Actual result:
--------------
array ( 
  'id_name' => '1', 
  'id_[name' => 'a',
)