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See also 
Developing plugins, 
Developer's Bible, 
Technical Overview
  internal package Foswiki::EngineException  is a Error 
Exception used to raise an engine related error. This exception has the
following fields: 
-  status- status code to send to client
-  reasona text string giving the reason for the refusal.
 ClassMethod new( $status, $reason [, $response] ) 
 
-  $status- status code to send to client
-  $reason- string reason for failure
-  $response- custom Foswiki::Response object to be sent to client. Optional.
All the above fields are accessible from the object in a catch clause
in the usual way e.g. 
$e→{status} and 
$e→{reason}
 ObjectMethod stringify() → $string 
Generate a summary string. This is mainly for debugging.