Tied Variables in the Template Toolkit

rlb3 has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks, I have been trying to use more of the MVC method for my web projects. To that end, I have be using the Template Toolkit a lot. On the this project I decided to use Class::DBI and Class::DBI::Pager. They work beautifully and I couldn’t be happier with them. The problem I am having is when I added Tie::Cycle to the mix. I pass the tied variable info my template, but only the first value is used. I’ve looked around a little and I haven’t seen any problem using ties in the template toolkit. Its probability something I am doing wrong, but I just don’t see it. Could someone point me in the right direction.

Thanks,

rlb3

PS. Code and Template found below.


#!/usr/bin/perl

use strict;
use warnings;

use lib qw /./;

use CGI;
use Data; #Class::DBI
use Template;
use Tie::Cycle;

my $q = CGI->new;
my $file = 'index.html';
my $tt = Template->new({ INCLUDE_PATH => 'template/' });
tie my $cycle, 'Tie::Cycle', [ qw( FFFFFF CCCCCC ) ];

my $page = $q->param('page') || 1;

my $pager = Data->pager(5,$page);
my @data  = $pager->retrieve_all;

my $vars = {
                data    =>      \@data,
                pager   =>      $pager,
                cycle   =>      $cycle
          };

print $q->header;
$tt->process($file, $vars)
        || die "Template process failed: ", $tt->error(), "\n";


BEGIN TEMPLATE-----------------------------------


<html>
        <head>
                <title></title>
        </head>
        <body>
                <table width="75%" border="0">
                        <tr>
                                <th>
                                        &nbsp;
                                </th>
                                <th>
                                        Question 1
                                </th>
                                <th>
                                        Question 2
                                </th>
                                <th>
                                        Question 3
                                </th>
                                <th>
                                        Date
                                </th>
                        </tr>
                        [% FOREACH line = data %]
                        <tr bgcolor="#[% cycle %]">
                                <td align="center">
                                        [% loop.count %]
                                </td>
                                <td align="center">
                 [% line.one %]
                                </td>
                                <td align="center">
                                        [% line.two %]
                                </td>
                                <td align="center">
                                        [% line.three %]
                                </td>
                                <td align="center">
                                        [% line.stamp %]
                                </td>
                                <td align="center">
                                        <a href="delete.pl?id=[% line.
+id %]">DELETE</a>
                                </td>
                        </tr>
                        [% END %]
                </table>
[% IF pager.previous_page %]
        <a href="index.pl?page=[% pager.previous_page %]">prev [% page
+r.entries_per_page %]</a> |
[% END %]
[% IF pager.next_page %]
         <a href="index.pl?page=[% pager.next_page %]">next [% pager.e
+ntries_per_page %]</a>
[% END %]
        </body>
</html>
[download]

Comment on Tied Variables in the Template Toolkit Download Code

Replies are listed 'Best First'.
•Re: Tied Variables in the Template Toolkit by merlyn (Sage) on Feb 24, 2004 at 03:37 UTC
Replace your Tie::Cycle with a coderef. TT will do the right thing and call the coderef to get the "current" value. -- Randal L. Schwartz, Perl hacker Be sure to read my standard disclaimer if this is a reply.	[reply]
Re: •Re: Tied Variables in the Template Toolkit by rlb3 (Deacon) on Feb 24, 2004 at 04:08 UTC
Merlyn, You are the MAN!!! Thanks so much.. rlb3	[reply]
Re^2: Tied Variables in the Template Toolkit by Anonymous Monk on Aug 24, 2004 at 13:15 UTC
What do you mean by coderef? Could you please give me an example or point me to some resources, googling didn't really help.	[reply]
Re^3: Tied Variables in the Template Toolkit by dragonchild (Archbishop) on Aug 24, 2004 at 13:25 UTC
coderef => reference to a subroutine. Also known as a subref. ------ We are the carpenters and bricklayers of the Information Age. Then there are Damian modules.... sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon.* - flyingmoose I shouldn't have to say this, but any code, unless otherwise stated, is untested	[reply]
Re: Tied Variables in the Template Toolkit by perrin (Chancellor) on Feb 24, 2004 at 03:14 UTC
The XS Stash doesn't support tied variables yet. You can use the normal (slower) Stash, or avoid tied variables (which are also slow, incidentally).	[reply]