NAME

       HTML::Template::Plugin::Dot - Add Magic Dot notation to HTML::Template

SYNOPSIS

         use HTML::Template::Pluggable;
         use HTML::Template::Plugin::Dot;

         my $t = HTML::Template::Pluggable->new(...);

       Now you can use chained accessor calls and nested hashrefs as params, and access them with
       a dot notation. You can even pass arguments to the methods.

       For example, in your code:

         $t->param( my_complex_struct => $struct );

       And then in your template you can reference specific values in the structure:

         my_complex_struct.key.obj.accessor('hash')
         my_complex_struct.other_key

DESCRIPTION

       By adding support for this dot notation to HTML::Template, the programmers' job of sending
       data to the template is easier, and designers have easier access to more data to display
       in the template, without learning any more tag syntax.

   EXAMPLES
   Class::DBI integration
       Class::DBI accessors can be used in the template.  If the accessor is never called in the
       template, that data doesn't have to be loaded.

       In the code:

         $t->param ( my_row => $class_dbi_obj );

       In the template:

         my_row.last_name

       This extends to related objects or inflated columns (commonly used for date fields).
       Here's an example with a date column that's inflated into a DateTime object:

         my_row.my_date.mdy('/')
         my_row.my_date.strftime('%D')

       Of course, if date formatting strings look scary to the designer, you can keep them in the
       application, or even a database layer to insure consistency in all presentations.

       Here's an example with related objects. Suppose you have a Customer object, that has_a
       BillingAddress object attached to it. Then you could say something like this:

         <tmpl_if customer.billing_address>
           <tmpl_var customer.billing_address.street>
           <tmpl_var customer.billing_address.city>
           ...
         </tmpl_if>

   More complex uses
       The dot notation allows you to pass arguments to method calls (as in the
       "my_date.dmy('/')" example above). In fact, you can pass other objects in the template as
       well, and this enables more complex usage.  Imagine we had a (fictional) Formatter object
       which could perform some basic string formatting functions. This could be used in e.g.
       currencies, or dates.

       In your code:

         $t->param( Formatter => Formatter->new,
                    order         => $order_obj     );

       In your template:

         Amount: <tmpl_var Formatter.format_currency('US',order.total_amount)>

       (hint: see Number::Format)

       This even extends to references to plain tmpl_vars in your template:

         $t->param( Formatter => Formatter->new,
                    plain     => 'Jane'         );

         <tmpl_var Formatter.reverse(plain)> is
         <tmpl_var plain> backwards

   TMPL_LOOPs
       As of version 0.94, the dot notation is also supported on TMPL_LOOP tags (but see the
       "LIMITATIONS" section).

       Given an object method (or a hash key) that returns an array or a reference to an array,
       we will unwrap that array for use in the loop. Individual array elements are mapped to a
       hash "{ 'this' => $elt }", so that you can refer to them in TMPL_VARs as "this.something".

       An example might help. Let's use the canonical Class::DBI example for our data.  Suppose
       you have an $artist object, which has_many CDs. You can now pass just the $artist object,
       and handle the loops in the template:

         $t->param( artist => $artist );

       The template:

         <tmpl_var artist.name> has released these albums:
         <tmpl_loop artist.cds>
           <tmpl_var this.title> - <tmpl_var this.year>
         </tmpl_loop>

       As you can see, each element from the artist.cds() array is called "this" by default. You
       can supply your own name by appending ': name' like this:

         <tmpl_loop artist.cds:cd>
           <tmpl_var cd.title>
           ...

       That's not the end of it! You can even nest these loops, displaying the Tracks for each CD
       like so:

         <tmpl_loop artist.cds:cd>
           <tmpl_var cd.title>
           <tmpl_loop cd.tracks:track>
             - <tmpl_var track.title> ( <tmpl_var track.tracktime> )
           </tmpl_loop>
         </tmpl_loop>

   LIMITATIONS
       •   Casing of parameter names

           Casing of parameter names follows the option "case_sensitive" of HTML::Template. If
           you do not use that option, all parameter names are converted to lower case. I suggest
           turning this option on to avoid confusion.

       •   Quotes and spaces

           Because of the way HTML::Template parses parameter names (which follows the rules of
           HTML attributes), you have to be careful when your expressions contain spaces or quote
           characters. You can say "<tmpl_var something.without.spaces>", but not "<tmpl_var
           something with spaces>". You can use single or double quotes around your entire
           expression, and then use the other one inside: "<tmpl_var name="some.method('with
           arguments')">" This is the recommended way to write your expressions.

           (Note: within expressions, the characters in "[`'"]" are recognised as quote
           characters. So if you need to pass literal quotes to a method, you could do it like
           this: "<tmpl_var name='some.method(`need a " here`)'>". )

   PERFORMANCE
       No attempt to even measure performance has been made. For now the focus is on usability
       and stability. If you carry out benchmarks, or have suggestions for performance
       improvements, be sure to let us know!

CONTRIBUTING

       Patches, questions and feedback are welcome. This project is managed using the darcs
       source control system ( http://www.darcs.net/ ). A public darcs archive is here:
       http://cgiapp.erlbaum.net/darcs_hive/ht-pluggable/

AUTHORS

       Mark Stosberg, <mark@summersault.com>; Rhesa Rozendaal, <rhesa@cpan.org>

Copyright & License

        Parts copyright 2006 Mark Stosberg
        Parts copyright 2006 Rhesa Rozendaal

       This program is free software; you can redistribute it and/or modify it under the same
       terms as perl itself.