2004-03-24 15:16:30 +00:00
										 
									 
								 
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								<?xml version="1.0" encoding="iso-8859-1"?>
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								<!-- $Revision$ -->
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											2004-03-18 17:16:23 +00:00
										 
									 
								 
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								 <preface id="preface">
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								  <title>Preface</title>
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								  <para>
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								   It is undoubtedly one of the most asked questions on the PHP mailing
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								   lists: how do I make my PHP scripts independent of the layout? While
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								   PHP is billed as "HTML embedded scripting language", after writing a
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								   couple of projects that mixed PHP and HTML freely one comes up with the
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								   idea that separation of form and content is a Good Thing [TM]. In
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								   addition, in many companies the roles of layout designer and programmer
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								   are separate. Consequently, the search for a templating solution
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								   ensues.
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								  </para>
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								  <para>
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								   In our company for example, the development of an application goes on
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								   as follows: After the requirements docs are done, the interface
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								   designer makes mockups of the interface and gives them to the
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								   programmer. The programmer implements business logic in PHP and uses
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								   interface mockups to create skeleton templates. The project is then
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								   handed off to the HTML designer/web page layout person who brings the
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								   templates up to their full glory. The project may go back and forth
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								   between programming/HTML a couple of times. Thus, it's important to
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								   have good template support because programmers don't want anything to
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								   do with HTML and don't want HTML designers mucking around with PHP
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								   code. Designers need support for config files, dynamic blocks and
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								   other interface issues, but they don't want to have to deal with
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								   intricacies of the PHP programming language.
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								  </para>
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								  <para>
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								   Looking at many templating solutions available for PHP today, most of
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								   them provide a rudimentary way of substituting variables into templates
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								   and do a limited form of dynamic block functionality. But our needs
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								   required a bit more than that. We didn't want programmers to be dealing
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								   with HTML layout at ALL, but this was almost inevitable. For instance,
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								   if a designer wanted background colors to alternate on dynamic blocks,
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								   this had to be worked out with the programmer in advance. We also
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								   needed designers to be able to use their own configuration files, and
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								   pull variables from them into the templates. The list goes on.
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								  </para>
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								  <para>
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								   We started out writing out a spec for a template engine back in late
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								   1999.  After finishing the spec, we began to work on a template engine
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								   written in C that would hopefully be accepted for inclusion with PHP.
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								   Not only did we run into many complicated technical barriers, but there
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								   was also much heated debate about exactly what a template engine should
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								   and should not do. From this experience, we decided that the template
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								   engine should be written in PHP as a class, for anyone to use as they
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								   see fit. So we wrote an engine that did just that and
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								   <productname>SmartTemplate</productname> came into existence (note: this
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								   class was never submitted to the public). It was a class that did
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								   almost everything we wanted: regular variable substitution, supported
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								   including other templates, integration with config files, embedding PHP
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								   code, limited 'if' statement functionality and much more robust dynamic
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								   blocks which could be multiply nested. It did all this with regular
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								   expressions and the code turned out to be rather, shall we say,
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								   impenetrable. It was also noticably slow in large applications from all
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								   the parsing and regular expression work it had to do on each
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								   invocation. The biggest problem from a programmer's point of view was
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								   all the necessary work in the PHP script to setup and process templates
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								   and dynamic blocks. How do we make this easier?
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								  </para>
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								  <para>
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								   Then came the vision of what ultimately became Smarty. We know how fast
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								   PHP code is without the overhead of template parsing. We also know how
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								   meticulous and overbearing the PHP language may look to the average
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								   designer, and this could be masked with a much simpler templating
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								   syntax. So what if we combined the two strengths? Thus, Smarty was
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											2005-05-27 16:25:02 +00:00
										 
									 
								 
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								   born... :-)
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											2004-03-18 17:16:23 +00:00
										 
									 
								 
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								  </para>
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								 </preface>
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								<!-- Keep this comment at the end of the file
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								Local variables:
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								mode: sgml
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								sgml-omittag:t
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								sgml-shorttag:t
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								sgml-minimize-attributes:nil
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								sgml-always-quote-attributes:t
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								sgml-indent-step:1
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								sgml-indent-data:t
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								indent-tabs-mode:nil
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								sgml-parent-document:nil
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								sgml-default-dtd-file:"../../../../manual.ced"
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								sgml-exposed-tags:nil
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								sgml-local-catalogs:nil
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								sgml-local-ecat-files:nil
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								End:
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								vim600: syn=xml fen fdm=syntax fdl=2 si
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								vim: et tw=78 syn=sgml
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								vi: ts=1 sw=1
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								-->
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