Template Toolkit does not allow recursively including template files, but you can use a VIEW to recurse over a data structure. VIEWs are still experimental but it works for me.
use Template;
use strict;
use warnings;

my $t = Template->new;
my @nodes = (
{name => "one"},
{name => "two", children => [ {name => "red"},
                              {name => "green"} ] },
{name => "three", children => [
  {name => "blah", children => [
    {name => "yakko" },
    {name => "wacko" },
    {name => "dot" }
   ]
  }
]
} );


$t->process("rec.tt", { nodes => \@nodes } );

[download]

And the template: 

[% VIEW nested_list %]
  [% BLOCK list %]
    <ul>
      [% FOREACH i IN item %]
        <li>[% i.name %]</li>
        [% IF i.children %]
          [% view.print(i.children.list) %]
        [% END %]
      [% END %]
    </ul>
  [% END %]
[% END %]

[% nested_list.print(nodes) %]

[download]

And that outputs:

Replies are listed 'Best First'.
Recursively display nested lists with Mason
by jeffa (Bishop) on Aug 29, 2006 at 15:42 UTC

    Very nice. If you don't mind, i'd like to add how to do this with HTML::Mason for posterity, contrast/compare, etc.

    Calling component (nodes.html) 

    <%init>
use strict;
use warnings;

my @nodes = (
    {name => "one"},
    {name => "two", children => [
        {name => "red"},
        {name => "green"},
    ] },
    {name => "three", children => [
        {name => "blah", children => [
            {name => "yakko" },
            {name => "wacko" },
            {name => "dot" },
        ] },
    ] },
);

$m->comp( 'nodes.mas', nodes => \@nodes );
</%init>

    [download]

    and nodes.mas 

    <%args>
@nodes
</%args>

<ul>
% foreach my $i (@nodes) {
    <li><% $i->{name} %></li>
%   if (ref( $i->{children} ) eq 'ARRAY') {
%       $m->comp( 'nodes.mas', nodes => $i->{children} );
%   }
% }
</ul>

    [download]
    I added a check to ref() for safety.

    jeffa

    L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)
[reply]
[d/l]
[select]
Re: Recursively display nested lists with Template Toolkit
by jasonk (Parson) on Sep 01, 2006 at 01:05 UTC

    Template Toolkit does allow templates to recurse, if you tell it to:

     RECURSION
   Flag to permit recursion into templates (default: 0).

    [download]
    We're not surrounded, we're in a target-rich environment!
[reply]
[d/l]
      Thanks, jasonk. For some reason I missed that in the docs.
[reply]
Re: Recursively display nested lists with Template Toolkit
by denny (Novice) on Jun 06, 2009 at 10:34 UTC
[reply]
Re: Recursively display nested lists with Template Toolkit
by ferz (Initiate) on Mar 24, 2012 at 19:57 UTC
    I don't understand where print() method (or MACRO) is defined.
[reply]

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