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NAME

Text::MicroMason::HTMLTemplate - Alternate Syntax like HTML::Template

SYNOPSIS

Instead of using this class directly, pass its name to be mixed in:

use Text::MicroMason;
my $mason = Text::MicroMason::Base->new( -HTMLTemplate );

Use the standard compile and execute methods to parse and evaluate templates:

print $mason->compile( text=>$template )->( @%args );
print $mason->execute( text=>$template, @args );

Or use HTML::Template's calling conventions:

$template = Text::MicroMason->new( -HTMLTemplate, filename=>'simple.tmpl' );
$template->param( %arguments );
print $template->output();

HTML::Template provides a syntax to embed values into a text template:

    <TMPL_IF NAME="user_is_dave">
      I'm sorry <TMPLVAR NAME="name">, I'm afraid I can't do that right now.
    <TMPL_ELSE>
      <TMPL_IF NAME="daytime_is_morning">
	Good morning, <TMPLVAR NAME="name">!
      <TMPL_ELSE>
	Good afternoon, <TMPLVAR NAME="name">!
      </TMPL_IF>
    </TMPL_IF>

DESCRIPTION

This mixin class overrides several methods to allow MicroMason to emulate the template syntax and some of the other features of HTML::Template.

This class automatically includes the following other mixins: TemplateDir, HasParams, and StoreOne.

Compatibility with HTML::Template

This is not a drop-in replacement for HTML::Template, as the implementation is quite different, but it should be able to process most existing templates without major changes.

This should allow current HTML::Template users to take advantage of MicroMason's one-time compilation feature, which in theory could be faster than HTML::Template's run-time interpretation. (No benchmarking yet.)

The following features of HTML::Template are not supported yet:

  • Search path for files. (Candidate for separate mixin class or addition to TemplateDir.)

  • Many HTML::Template options are either unsupported or have different names and need to be mapped to equivalent sets of attributes. (Transform these in the new() method or croak if they're unsupported.)

The following features of HTML::Template will likely never be supported due to fundamental differences in implementation:

  • query() method

Contributed patches to more closely support the behavior of HTML::Template would be welcomed by the author.

Template Syntax

The following elements are recognized by the HTMLTemplate lexer:

  • literal_text

    Anything not specifically parsed by the below rule is interpreted as literal text.

  • <TMPL_tagname>

    A template tag with no attributes.

  • <TMPL_tagname varname>

    A template tag with a name attribute.

  • <TMPL_tagname NAME=varname option=value ...>

    A template tag with one or more attributes.

  • </TMPL_tagname>

    A closing template tag.

The following tags are supported by the HTMLTemplate assembler:

tmpl_var

<tmpl_var name=... ( default=... ) ( escape=... ) >

tmpl_include

<tmpl_include name=... >

tmpl_if

<tmpl_if name=... > ... </tmpl_if>

tmpl_unless

<tmpl_unless name=...> ... </tmpl_unless>

tmpl_else

<tmpl_else>

tmpl_loop

<tmpl_loop name=...> ... </tmpl_loop>

Supported Attributes

associate

Optional reference to a CGI parameter object or other object with a similar param() method.

loop_global_vars (HTML::Template's "global_vars")

If set to true, don't hide external parameters inside a loop scope.

loop_context_vars

If set to true, defines additional variables within each <TMPL_LOOP>: __counter__, which specifies the row index, and four boolean flags, __odd__, __first__, __inner__, and __last__.

Public Methods

new()

Creates a new Mason object. If a filename parameter is supplied, the corresponding file is compiled.

param()

Gets and sets parameter arguments. Similar to the param() method provied by HTML::Template and the CGI module.

output()

Executes the most-recently compiled template and returns the results.

Optionally accepts a filehandle to print the results to.

$template->output( print_to => *STDOUT );

Private Methods

lex_token
( $type, $value ) = $mason->lex_token();

Lexer for <TMPL_x> tags.

Attempts to parse a token from the template text stored in the global $_ and returns a token type and value. Returns an empty list if unable to parse further due to an error.

parse_args()

Lexer for arguments within a tag.

assemble_tmpl_*()

These methods define the mapping from the template tags to the equivalent Perl code.

filter()

Used to implement the escape option for tmpl_var.

SEE ALSO

The interface being emulated is described in HTML::Template.

For an overview of this templating framework, see Text::MicroMason.

This is a mixin class intended for use with Text::MicroMason::Base.

For distribution, installation, support, copyright and license information, see Text::MicroMason::Docs::ReadMe.