Re: [htmltmpl] H-T strangeness with CGI-Session

[Puneet K. <pk...@ei...>]

Cees Hek wrote:

> Puneet Kishor wrote:
> 
>> The problem is thus -- I am storing only the identifying info and a 
>> descriptive text. But the AofH in the Session file is showing 
>> additional info that looks suspiciously like the loop_context_vars. 
>> Here is an excerpt from my Session file --
>>
>> "rolodex" => [{"ROLODEXVAL" => 3330,"__last__" => 0,"ROLODEXTEXT" => 
>> "Puneet Kishor (My Org, Inc.)","__counter__" => undef,"__first__" => 
>> 0,"__odd__" => 0,"__inner__" => 0}],
> 
> 
> This is probably because you are passing a reference to a data structure 
> to both CGI::Session and HTML::Template.  In other words they both get 
> the exact in memory data structure.  HTML::Template is adding things to 
> the hashes that are stored in the array ref, and CGI::Session doesn't 
> save it's parameters to the session until it goes out of scope (probably 
> at the end of the request) so it sees the changes that HTML::Template 
> made to the data.
> 
> There are a couple of things you can do to solve it.
> 
> - Don't pass the same data structure to both CGI::Session and 
> HTML::Template.  Make a copy of the data before passing it by 
> dereferencing the data (see the dclone() method in the Storable module 
> for copying complex data structures if you have a deep data structure).
> 
> - Or you can make CGI::Session save it's data right away by making it go 
> out of scope, or calling close or flush to sync the data to the session 
> store.
> 
> Although HTML::Template is causing this problem, I don't think you cna 
> call it a bug.  Although many modules will make a copy of the data that 
> is passed in if they intend to make any changes, that can be very 
> expensive if there is a lot of data (which there tends to be when 
> dealing with templates).
> 


That explains it. You hit it right on the nose, Cees. It is indeed 
happening because I am sending the same ref to the AofH. Thanks much for 
you advice as I now know how to solve it.

Puneet.