NAME

HTML::Template::JIT - a just-in-time compiler for HTML::Template

SYNOPSIS

  use HTML::Template::JIT;

  my $template = HTML::Template::JIT->new(filename => 'foo.tmpl',
                                          jit_path => '/tmp/jit',
                                         );
  $template->param(banana_count => 10);
  print $template->output();

DESCRIPTION

This module provides a just-in-time compiler for HTML::Template. The module works in two phases:

Load

When new() is called the module checks to see if it already has an up-to-date version of your template compiled. If it does it loads the compiled version and returns you a handle to call param() and output().

Compile

If your template needs to be compiled - either because it has changed or because it has never been compiled - then HTML::Template::JIT loads HTML::Template::JIT::Compiler which uses HTML::Template and Inline::C to compile your template to native machine instructions.

The compiled form is saved to disk in the jit_path directory and control returns to the Load phase.

This may sound a lot like the way HTML::Template's cache mode works but there are some significant differences:

The compilation phase takes a long time. Depending on your system it might take several of seconds to compile a large template.
The resulting compiled template is much faster than a normal cached template. My benchmarks show HTML::Template::JIT, with a precompiled template, performing 4 to 8 times faster than HTML::Template with in cache mode.
The resulting compiled template should use less memory than a normal cached template. Also, if all your templates are already compiled then you don't even have to load HTML::Template to use the templates!

USAGE

Usage is the same as normal HTML::Template usage with a few addition new() options. The new options are:

jit_path: This is the path that the module will use to store compiled modules. It needs to be both readable and writeable. This directory will slowly grow over time as templates are changed are recompiled so you might want to periodically clean it out. HTML::Template::JIT might get better at cleaning-up after itself in a future version.
no_compile: This option tells the module to never compile templates. If it can't find a compiled version of a template then it croak()s rather than load HTML::Template::JIT::Compiler. You might want to use this option if you've precompiled your templates and want to make sure your users are never subjected to the lag of a compiler run.
jit_debug: Spits out a bunch of obscure debugging on STDERR.

CAVEATS

This version is rather limited. It doesn't support the following options:

   cache (all modes)
   associate
   case_sensitive
   print_to
   scalarref (and friends)
   arrayref  (and friends)
   die_on_bad_params

Included files are not checked for changes when checking a compiled template for freshness.

CODE-ref params are not supported.

The query() method is not supported.

It's not as fast as it could be - I'd like to see it reach somewhere around 10x faster than normal HTML::Template.

As development progresses I hope to eventually address all of these limitations.

BUGS

When you find a bug, join the mailing list and tell us about it (htmltmpl@lists.vm.com) You can join the HTML::Template mailing-list by sending a blank email to htmltmpl-subscribe@lists.vm.com. Of course, you can still email me directly (sam@tregar.com) with bugs, but I reserve the right to forward bug reports to the mailing list.

When submitting bug reports, be sure to include full details, including the VERSION of the module, a test script and a test template demonstrating the problem!

AUTHOR

Sam Tregar <sam@tregar.com>

LICENSE

HTML::Template::JIT : Just-in-time compiler for HTML::Template

This module is free software; you can redistribute it and/or modify it under the terms of either:

a) the GNU General Public License as published by the Free Software Foundation; either version 1, or (at your option) any later version, or

b) the ``Artistic License'' which comes with this module.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See either the GNU General Public License or the Artistic License for more details.

You should have received a copy of the Artistic License with this module, in the file ARTISTIC. If not, I'll be glad to provide one.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA