Twig

Twig lets you use the Twig template engine in your WordPress themes. It's very easy to use but still very powerful.

Author:	Martin Pettersson (profile at wordpress.org)
WordPress version required:	3.0.1
WordPress version tested:	4.0
Plugin version:	1.0.2
Added to WordPress repository:	28-07-2014
Last updated:	13-10-2014 Warning! This plugin has not been updated in over 2 years. It may no longer be maintained or supported and may have compatibility issues when used with more recent versions of WordPress.
Rating, %:	0
Rated by:	0
Plugin URI:	http://github.com/martin-pettersson/WP_Twig
Total downloads:	462
Active installs:	10+
Click to start download

This WordPress plugin allows you to use the Twig template engine in your WordPress themes. It is really simple to use and even includes a template wrapper enabling you to use a master layout file to keep your themes D.R.Y.

Usage

Let's start with the most simple use of this plugin to get you going:

<?php // index.php

Twig::View();

And that's it! The plugin will automatically know that you are in the index.php file, and try to find the template index.twig in any of the specified template folders. We will later see how we can use this principle in a very creative manner.

Of course we can specify wich template to use, we do this without the file extension like so:

Twig::View([
    'template' => 'post'
]);

The plugin will now look for the template post.twig.

Template folder structure

You can offcourse keep all your templates organized into folders and render them like so:

Twig::View([
    'template' => 'components/header'
]);

Twig::View([
    'template' => 'index'
]);

Twig::View([
    'template' => 'components/footer'
]);

If you find this an interesting aproach please read about template wrapping below.

Passing variables to templates

To pass variables to our templates you pass the view function a context parameter. The context parameter is an array of variables of your choice:

// define variables to pass on to template
$name = 'Martin';
$age = 26;

$footer_context = [
    'author' => $name,
    'date' => date('Y-m-d')
];

Twig::View([

    'template' => 'components/header',

    // pass on variables to use in template
    'context' => [
        'title' => 'Twig'
    ]
]);

Twig::View([

    'template' => 'index',

    // pass on variables to use in template
    'context' => [
        'name' => $name,
        'age' => $age
    ]
]);

Twig::View([

    'template' => 'components/header',

    // pass on variables to use in template
    'context' => $footer_context
]);

The variables we passed on are now available in the templates like so:

{# index.twig #}
<p>My name is {{ name }} and I am {{ age }} years old!</p>

This clearly shows how we can use the WordPress template files (ex. index.php) to handle all our logic and let the Twig template engine do what it does best.

Remember Twig

Don't forget that you are using Twig. You can still use the awesome features of Twig such as: multiple inheritance, blocks, automatic output-escaping etc.

Template hierarchy

This plugin utilizes WordPress template hierarchy in a very neat whay. Ex:

Twig::View( ['template' =>'page-about'] );

The plugin will try to find the template page-about.twig and gracefully fall back to page.twig if it does'nt exist. It will actually fall back like this:

page-about-me.twig -> page-about.twig -> page.twig

. Which will be very handy when we use master layout files.

Template wrapping

The plugin comes with a simple template wrapper. It allows you to specify a master layout file: _layout.php and exposes two new functions:

/**
 * returns the WordPress template being rendered
 * 
 * Ex: index, page, page-about
 */
get_twig_template();

/**
 * returns the absolute path of the same template
 *
 * Ex: ABSPATH/wp-content/themes/active-theme/index.php
 */
get_twig_template_path();

If we've enabled this feature in the admin section we can now create the file _layout.php in our theme folder and it might look like this:

<?php // _layout.php

get_header( get_twig_template() );

include get_twig_template_path();

get_footer( get_twig_template() );

WordPress will now attempt to include header.php, the WordPress template (ex. index.php) and the footer.php. Notice that doing this allows us to make the get_header() and get_footer() calls only once. We can now focus on the contents of our WordPress template files, and the header and footer files will be automatically included. Because of the two new functions, if we have a file called header-page.php in our theme. It will be included when we visit a WordPress 'page'.

Template wrapper hierarchy

The (second) best thing about the template wrapper is that it also follows the template hierarchy. Thus we can create the file: _layout-page.php and it will we used when visiting a WordPress 'page'. We can even create the file: _layout-page-about.php and it will be used on our about page.

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