NYCPHP Meetup

[paul at devonianfarm.com]

I've been all over the map.  Years ago I was against templating systems,  then I was a big fan of smarty,  now my templating strategy is the one that's used in symfony:  don't use a separate templating system,  but impose some discipline on the way you use PHP.

My answer would be different in languages that aren't as facile as PHP...  I would use a templating system in Perl, Java or Ruby,  but in a systems PHP,  ColdFusion or ASP.NET,  which were designed from the beginning to build web apps,  it's hard to develop a templating system which is better than the one the language gives you.

Study the "view" part of the symfony docs if you want to get a good picture of how do this,  but you don't need a heavyweight framework to get the benefits...  I built an MVC "microframework" in 80 lines of PHP and wrote another 120 lines worth of helper functions that dealt with common annoyances such as populating <select> lists.  The big concepts are:

* layouts: you need some mechanism for selecting a "master template" that your page appears in.  This looks like

<html>
   <head>...<title><?php q($title) ?></title>...
</head>
<body>
 ... header stuff ...
 <?php echo $real_content ?>
 ... footer stuff ...
</body>
</html>

Note that the master template is real HTML (<?php is a processing instruction) so you (or a designer) can edit it in dreamweaver or your favorite tools.

* partials: a partial is a PHP file that emits HTML that goes into slots like the $real_content slot...  With output buffering (see the ob_start function) you can capture the output of a PHP "template" and put it in a string for further processing.  With some work you can do this recursively,  so partials end up inside partials.

* helpers: these are functions that help you write views.  For instance, the q() function above is

function q($string) {
   echo(htmlspecialchars($q));
}

You'll need helpers to make form elements for you,  for instance,  something like

draw_select_list($name,$options,$selected)

where the $options are an associative array of values and display text.

Symfony has a mature view system that has caching and other advanced features (I wish I could say it was as mature in the data access department)

For my day job I'm working on an ASP.NET microframework that uses the same ideas.

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Paul Houle
http://animalphotos.info/a/