http://blog.leetsoft.com/articles/2005/11/05/introducing-liquid

Transparent, Unified Access

1. don’t have to write all those toArray() method to dump your data to Smarty
2. can lazy load data as needed
3. can provide intelligent formatting without the need to write a Smarty plugin

(fyi this “ideal world” is also known as Template Toolkit)

SPL

A quick example (there are probably better ones)

Say you had a class that you used to help you page through a list of results, and at the bottom of each page you wanted to add a slug like “Widgets 21-30 of 142″.

One solution would be to assign {$objectType}, {$showingMin}, {$showingMax}, {$totalToShow} (or some such) variables to Smarty, and then have something like the following in your template:

{$objectType} {$showingMin}-{$showingMax} of {$totalToShow} in

But to my eye that seems to clutter up the paging code with assigns, and clutter up the templates with unintuitive markup. (and this is a simple case)

Another solution would be to build the string at some point in your code, and pass that to Smarty (making your eventual I18N process just that much more challenging)

The third solution is to have your Pager class pretend to be an array, allowing you to add {$page.showStatus} to your templates which Smarty will compile into $this->tplvars['page']['showStatus'], and the SPL will intercept and transform into $page->offsetGet('showStatus');

So whats does the Pager class look like? Well the relevant bits look like:

class Pager implements ArrayAccess {
   ...
   function offsetGet($k) {
    if ($this->offsetExists($k)) {
                return $this->$k();
        }
   }


function offsetExists($k) {
       return method_exists($this, $k);
   }

/* set and unset don't do anything */

   function offsetSet($k, $v) {}
   function offsetUnset($k) {}

function showStatus() {
      ...construct status string and return it....
   }
}

A Word About Security

• strip all non-word characters from your access key like so: $key = preg_replace('/\W/', '', $key);
• the method calls are already namespaced to the object, but you could quarantine them further by appending a string to them (e.g. ‘tmpl‘), in which case your offsetGet() becomes

     function offsetGet($k) {
          $k = pregreplace('/\W/', '', $k);
      $f = "tmpl$f";
          return $this->$f();
     }
  

  (alternately you could use Relection API to limit offsetGet to only exposing methods inherited from some base class, or whatever other creative solution strikes your fancy)

Slouching towards release, part 2

• New and better error handling. Its not very PHP like, but its rationale, and flexible, and designed to be used as part of a larger application. (like I said, not very PHP like)
• more and better examples on how to use Magpie, including how to use it with Smarty
• Ships with a custom Smarty plugin for parsing RSS dates so you can include in your templates the nifty construct:

  $item.dc.date|rss_date_parse|date_format:"%A, %B %e, %Y"}

I think the biggest strength of a system like Movable Type is that the templating system is so powerful and easy to use. Is there any PHP based CMS/weblogging tool that uses templates in a way even close to how Movable Type does?

To which aaron responded:

php does have a decent template system called ‘Smarty’

And I’ll be the first to step up and agree, Smarty is a fine tool, it lacks the amazing flexibility and elegance of Template Toolkit, but thats frosting, and it stacks up nicely compared to Velocity and Cheetah. (more on this theme)

That said, its nothing remotely like Moveable Type’s template system, which I find novel and nearly perfect. As a programmer, with Template Toolkit at my fingers, I tend to think of a template as procedural language for describing presentation. This is the same idea behind PHP and JSP.

MT does something totally different, it defines a domain specific templating language for laying out a blog. I’ve read about domain specific languages in school, but its not until seeing both how elegant, and powerful it can be did I finally understand the appeal. (I’m still not willing to concede the point that Haskell is just plain weird) This is the same idea as JSP’s Taglibs, but without the ugly syntax.

I occasionally run into the limits MT’s language, wishing I had a more flexible conditional, or not operator, but it makes more sense then any approach I’ve seen, and I’m trying to incorporate it into the Protest.net rewrite.

ps. PHP does have ImageMagick bindings, check out the new PHP Imagemagick extension.