smarty/doc.sgm

<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook V3.1//EN">
<book>
<bookinfo>
	<title>Smarty - the compiling PHP template engine</title>
	<author>
		<firstname>Monte</firstname><surname>Ohrt</surname>
		<affiliation>
			<address><email>monte@ispi.net</email></address>
		</affiliation>
	</author>
	<author>
		<firstname>Andrei</firstname><surname>Zmievski</surname>
		<affiliation>
			<address><email>andrei@ispi.net</email></address>
		</affiliation>
	</author>
	<copyright><year>2001</year><holder>ispi, Inc.</holder></copyright>
</bookinfo>
<chapter>
	<title>Overview</title>
		<para>
		It is undoubtedly one of the most asked questions on the PHP mailing
		lists: how do I make my PHP scripts independent of the layout? While
		PHP is billed as "HTML embedded scripting language", after writing a
		couple of projects that mixed PHP and HTML freely one comes up with the
		idea that separation of form and content is a Good Thing [TM]. In
		addition, in many companies the roles of layout designer and programmer
		are separate. Consequently, the search for a templating solution
		ensues.
		</para>
		<para>
		In our company for example, the development of an application goes on
		as follows: After the requirements docs are done, the interface
		designer makes mockups of the interface and gives them to the
		programmer. The programmer implements business logic in PHP and uses
		interface mockups to create skeleton templates. The project is then
		handed off to the HTML designer/web page layout person who brings the
		templates up to their full glory. The project may go back and forth
		between programming/HTML a couple of times. Thus, it's important to
		have good template support because programmers don't want anything to
		do with HTML and don't want HTML designers mucking around with PHP
		code. Designers need support for config files, dynamic blocks and other
		stuff, but they don't want to have to deal with intricacies of the PHP
		programming language.
		</para>
		<para>
		Looking at many templating solutions available for PHP today, most of
		them provide a rudimentary way of substituting variables into templates
		and do a limited form of dynamic block functionality. But our needs
		required a bit more than that. We didn't want programmers to be dealing
		with HTML layout at ALL, but this was almost inevitable. For instance,
		if a designer wanted background colors to alternate on dynamic blocks,
		this had to be worked out with the programmer in advance. We also
		needed designers to be able to use their own configuration files, and
		pull variables from them into the templates. The list goes on.
		</para>
		<para>
		We started out writing out a spec for a template engine about a year
		ago.  After finishing the spec, we began to work on a template engine
		written in C that would hopefully be accepted for inclusion with PHP.
		Not only did we run into many complicated technical barriers, but there
		was also much heated debate about exactly what a template engine should
		and should not do. From this experience, we decided that the template
		engine should be written in PHP as a class, for anyone to use as they
		see fit. So we wrote an engine that did just that and
		<emphasis>SmartTemplate</emphasis> came into existence (note: this
		class was never submitted to the public). It was a class that did
		almost everything we wanted: regular variable substitution, supported
		including other templates, integration with config files, embedding PHP
		code, limited 'if' statement functionality and much more robust dynamic
		blocks which could be multiply nested. It did all this with regular
		expressions and the code turned out to be rather, shall we say,
		impenetrable. It was also noticably slow in large applications from all
		the parsing and regular expression work it had to do on each
		invocation. The biggest problem from a programmer's point of view was
		all the necessary work in the PHP script to setup and process templates
		and dynamic blocks. How do we make this easier?
		</para>
		<para>
		Then came the vision of what ultimately became Smarty. We know how fast
		PHP code is without the overhead of template parsing. We also know how
		meticulous and overbearing the PHP language may look to the average
		designer, and this could be masked with a much simpler templating
		syntax. So what if we combined the two strengths? Thus, Smarty was
		born...
		</para>
	<sect1><title>What is Smarty?</title>
		<para>
		Smarty is a template engine for PHP. One of the unique aspects about
		Smarty that sets it apart from other templating solutions is that it
		compiles the templates into native PHP scripts upon the first
		invocation. After that, it merely executes the compiled PHP scripts.
		Therefore, there is no costly template file parsing for each request.
		</para>
		<para>
		Some of Smarty's features:
		</para>
		<itemizedlist>
		<listitem><para>It is extremely fast.</para></listitem>
		<listitem><para>It is efficient since the PHP parser does the
			dirty work.</para></listitem>
		<listitem><para>No template parsing overhead, only compiles once.</para></listitem>
		<listitem><para>It is smart about recompiling only the template
			files that have changed.</para></listitem>
		<listitem><para>You can make <link linkend="custom.functions">custom
			functions</link> and custom <link linkend="variable.modifiers">variable
			modifiers</link>, so the template language is extremely extensible.</para></listitem>
		<listitem><para>Configurable template delimiter tag syntax, so you can use
			{}, {{}}, &lt;!--{}--&gt;, or whatever you like.</para></listitem>
		<listitem><para>The if/elseif/else/endif constructs are passed to the
			PHP parser, so the if expression syntax can be as simple or as complex
			as you like.</para></listitem>
		<listitem><para>Unlimited nesting of sections, ifs, etc. allowed.</para></listitem>
		<listitem><para>It is possible to embed PHP code right in your template files,
			although this may not be needed (nor recommended)
			since the engine is so customizable.</para></listitem>
		</itemizedlist>
	</sect1>
	<sect1>
		<title>How Smarty works</title>
		<sect2><title>Compiling</title>
			<para>
			Smarty compiles the templates into native PHP code on-the-fly. The actual
			PHP scripts that are generated are created implicitly, so theoretically you
			should never have to worry about touching these files, or even know of their
			existence. The exception to this is debugging Smarty template syntax errors,
			discussed later in this document.
			</para>
		</sect2>
		<sect2><title>Caching</title>
		<para>
			Our initial intention was to build caching into Smarty. However,
			since the template engine is actually executing PHP scripts instead of
			parsing template files, the need for a cache was dramatically reduced.
			We may implement this in a future version of Smarty as the need arises.
		</para>
		</sect2>
	</sect1>
</chapter>
<chapter>
	<title>Installation</title>
	<sect1>
		<title>Requirements</title>
		<para>
		Smarty requires PHP 4 or later. See the
		<link linkend="bugs">BUGS</link> section for caveats.
		</para>
	</sect1>
	<sect1>
		<title>Installing Smarty</title>
		<para>
		Installing Smarty is fairly straightforward, there is just one thing
		you must be aware of. Remember that Smarty creates compiled versions of
		the template code.  This usually means allowing user "nobody" (or
		whomever the web server runs as) to have permission to write the files.
		Each installation of a Smarty application minimally needs a templates
		directory and a compiled templates directory. If you use configuration
		files you will also need a directory for those. By default these are
		named "templates", and "templates_c" and "configs" respectively.
		</para>
		<para>
		Copy the Smarty.class.php, Smarty.addons.php and Config_File.class.php
		scripts to a directory that is in your PHP include_path. NOTE: PHP will
		try to create a directory alongside the executing script called
		"templates_c". Be sure that directory permissions allow this to happen.
		You will see PHP error messages if this fails. You can also create the
		directory yourself before hand, and change the file ownership
		accordingly. See below.
		</para>
		<example>
			<title>Example of installing Smarty</title>
<programlisting>

# be sure you are in the web server document tree
# this assumes your web server runs as user "nobody"
# and you are in a unix environment
gtar -zxvf Smarty-1.0.tar.gz
mkdir templates_c
chown nobody:nobody templates_c
</programlisting>
		</example>
		<para>
		Next, try running the index.php script from your web browser.
		</para>
	</sect1>
</chapter>
<chapter>
	<title>Setting up Smarty</title>
		<para>
		There are several variables that are at the top of the Smarty.class.php
		file. You can usually get away with leaving these at their default
		settings. This is a list of them and what each one does.
		</para>
	<sect1>
		<title>Configuration variables</title>
		<para></para>
		<sect2>
			<title>$compile_check</title>
			<para>
				Upon each invocation of the PHP application, Smarty recursively
				traverses the template directory and its subdirectories and
				searches for all the files with the template extension that
				have changed (later time stamp) since the last time they were
				compiled. For each one that has changed, it recompiles that
				template. By default this variable is set to true. The compile
				check has very minimal impact on the application performance.
				However, once an application is put into production and it is
				initially compiled, the compile_check step is no longer needed.
				You may set this to "false" *after* the initial compile. Then
				Smarty will no longer check for changed template files. Note
				that if you change this to "false" and a template file is
				changed, you will *not* see the change since the template will
				not get recompiled. Set it to "true", invoke the application,
				then set it back to "false".
			</para>
		</sect2>
		<sect2>
			<title>$template_dir</title>
			<para>
				This is the directory where template files are located.
			</para>
		</sect2>		
		<sect2>
			<title>$compile_dir_ext</title>
			<para>
				This is the extension used for the name of the directory where
				compiled templates are located. By default this is "_c".
				Therefore if your template directory is named "templates", then
				the compiled templates directory will be named "templates_c".
			</para>
		</sect2>
		<sect2>
			<title>$tpl_file_ext</title>
			<para>
				This is the extention used for template files. By default this
				is ".tpl". All other files in the template directory are
				ignored.
			</para>
		</sect2>
		<sect2>
			<title>$allow_php</title>
			<para>
				Whether or not to allow PHP code in the templates. If set to
				false, PHP code is escaped and not interpreted. Embedding PHP
				code into templates is highly discouraged. Use custom functions
				or <link linkend="variable.modifiers">modifiers</link> instead. Default is "false".
			</para>
		</sect2>
		<sect2>
			<title>$left_delimiter</title>
			<para>
				This is the left delimiter used by the template language. Default is "{".
			</para>
		</sect2>
		<sect2>
			<title>$right_delimiter</title>
			<para>
				This is the right delimiter used by the template language. Default is "}".			
			</para>
		</sect2>
		<sect2>
			<title>$config_dir</title>
			<para>
				This is the directory used to store config files used in the templates.
				Default is "configs".
			</para>
		</sect2>
		<sect2>
			<title>$custom_funcs</title>
			<para>
				This is a mapping of the names of custom functions in the template to
				the names of functions in PHP. These are usually kept in Smarty.addons.php.
			</para>
		</sect2>
		<sect2>
			<title>$custom_mods</title>
			<para>
				This is a mapping of the names of variable
				<link linkend="variable.modifiers">modifiers</link> in the template to
				the names of functions in PHP. These are usually kept in Smarty.addons.php.			
			</para>
		</sect2>
		<sect2>
			<title>$global_assign</title>
			<para>
				This is a list of variables that are always implicitly assigned to the
				template engine. This is usually handy for making global variables or server
				variables available to the template without having to manually assign them to
				the template every time.
			</para>
		</sect2>
	</sect1>
</chapter>
<chapter>
	<title>Smarty API</title>
	<para>
		These functions are used in the PHP portion of your application.
	</para>
	<sect1>
		<title>Smarty API Functions</title>
		<sect2>
			<title>assign</title>
			<funcsynopsis>
			<funcprototype>
			<funcdef>void <function>assign</function></funcdef>
				<paramdef>mixed <parameter>var</parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<funcsynopsis>
			<funcprototype>
			<funcdef>void <function>assign</function></funcdef>
				<paramdef>string <parameter>varname</parameter></paramdef>
				<paramdef>mixed <parameter>var</parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<para>
				This is used to assign values to the templates. This is usually
				data gathered from database queries or other sources of data.
			</para>
		</sect2>
		<sect2>
			<title>append</title>
			<funcsynopsis>
			<funcprototype>
			<funcdef>void <function>append</function></funcdef>
				<paramdef>mixed <parameter>var</parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<funcsynopsis>
			<funcprototype>
			<funcdef>void <function>append</function></funcdef>
				<paramdef>string <parameter>varname</parameter></paramdef>
				<paramdef>mixed <parameter>var</parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<para>
				This is used to append data to existing variables in the template.
			</para>
		</sect2>
		<sect2>
			<title>clear_assign</title>
			<funcsynopsis>
			<funcprototype>
			<funcdef>void <function>clear_assign</function></funcdef>
				<paramdef>string <parameter>var</parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<para>
				This clears the value of an assigned variable.
			</para>
		</sect2>
		<sect2>
			<title>clear_all_assign</title>
			<funcsynopsis>
			<funcprototype>
			<funcdef>void <function>clear_all_assign</function></funcdef>
				<paramdef><parameter></parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<para>
				This clears the values of all assigned variables.
			</para>
		</sect2>
		<sect2>
			<title>get_template_vars</title>
			<funcsynopsis>
			<funcprototype>
			<funcdef>array <function>get_template_vars</function></funcdef>
				<paramdef><parameter></parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<para>
				This gets an array of the currently assigned template vars.
			</para>
		</sect2>
		<sect2>
			<title>display</title>
			<funcsynopsis>
			<funcprototype>
			<funcdef>void <function>display</function></funcdef>
				<paramdef>string <parameter>template</parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<para>
				This displays the template.
			</para>
		</sect2>
		<sect2>
			<title>fetch</title>
			<funcsynopsis>
			<funcprototype>
			<funcdef>string <function>fetch</function></funcdef>
				<paramdef>string <parameter>template</parameter></paramdef>
			</funcprototype>
			</funcsynopsis>
			<para>
				This returns the template output.
			</para>
		</sect2>
		<sect2>
		<title>Using Smarty API</title>
		<example>
			<title>Example use of Smarty API</title>
<programlisting>

include("Smarty.class.php");
$smarty = new Smarty;

// dummy up some data
$address = "245 N 50th";
$db_data = array(
	"City" => "Lincoln",
	"State" => "Nebraska",
	"Zip" = > "68502"
	);

$smarty->assign("Name","Fred");
$smarty->assign("Address",$address);
$smarty->assign($db_data);

// display the output
$smarty->display("./templates/index.tpl");

// alternatively capture the output
$output = $smarty->fetch("./templates/index.tpl");
</programlisting>
		</example>
		</sect2>
	</sect1>
</chapter>
<chapter>
	<title>Smarty Templates</title>
	<para>
	The templates are the heart of Smarty. These are the files that the designers
	work with. They're basically pages made up of static content interspersed with
	template markup tags. These tags are placeholders for variables or blocks of logic.
	</para>
	<sect1>
		<title>Syntax</title>
		<para>
			For these examples, we will assume that you are using the default
			template tag delimiters, which are "{" and "}". In Smarty, all content
			outside of delimiter tags is displayed as static content, or unchanged.
			When Smarty encounters template tags {}, it attempts to interpret what is
			between the tags, and displays the appropriate output in place of them.
		</para>
		<sect2>
			<title>Variables</title>
			<para>
			There are three basic types of variables in Smarty, each with their
			own unique syntax.
			</para>
			<sect3>
				<title>Variables assigned from PHP</title>
				<para>
				Variables that are assigned from PHP are displayed by preceeding
				them with a dollar sign ($) and enclosing the variable in delimiters
				like so: {$varname}
				</para>
<example>
<title>Template example of displaying assigned variables</title>
<programlisting>

Hello {$firstname}, glad to see you could make it.
&lt;p&gt;
Your last login was on {$lastLoginDate}.

OUTPUT:

Hello Doug, glad to see you could make it.
&lt;p&gt;
Your last login was on January 11th, 2001.
</programlisting>
</example>
				<para>
				There are also variables within looping sections that are displayed
				a bit differently. Those are exaplained later in this document under
				<link linkend="builtin.functions">Built-in Functions</link>.
				</para>
			</sect3>
			<sect3>
				<title>Variables passed from config files</title>
				<para>
				Variables that are passed in from config files are displayed by enclosing
				them with hash marks (#) and enclosing the variable in delimiters
				like so: {#varname#}
				</para>
<example>
<title>Template example of displaying config variables</title>
<programlisting>

&lt;html&gt;
&lt;title&gt;{#pageTitle#}&lt;/title&gt;
&lt;body bgcolor="{#bodyBgColor#}"&gt;
&lt;table border="{#tableBorderSize#}" bgcolor="{#tableBgColor#}"&gt;
	&lt;tr bgcolor="{#rowBgColor#}"&gt;
		&lt;td&gt;First&lt;/td&gt;
		&lt;td&gt;Last&lt;/td&gt;
		&lt;td&gt;Address&lt;/td&gt;
	&lt;/tr&gt;
&lt;/table&gt;
&lt;/body&gt;
&lt;/html&gt;
</programlisting>
</example>
				<para>
				Config file variables cannot be displayed until
				after they are loaded in from a config file. This procedure is
				explained later in this document under
				<link linkend="builtin.functions.configload">config_load</link>.
				</para>
			</sect3>
			<sect3>
				<title>Variables internal to template</title>
				<para>
				Variables that are internal to the templates are displayed by enclosing
				them with percent signs (%) and enclosing the variable in delimiters
				like so: {%varname%} So far, section properties are the only internal
				variables used in Smarty, which can be found later in this document under
				<link linkend="builtin.functions.section">section</link>.
				</para>
			</sect3>
		</sect2>
		<sect2>
			<title>Functions</title>
			<para>
			Functions are processed and displayed by enclosing the function and its
			attributes into delimiters like so: {funcname attr1="val" attr2="val"}
			</para>
<example>
<title>Template example of function syntax</title>
<programlisting>

{config_load file="colors.conf"}

{include file="header.tpl"}

{if $name eq "Fred"}
	You are not allowed here
{else}
	Welcome, &lt;font color="{#fontColor#}"&gt;{$name}!&lt;/font&gt;
{/if}

{include file="footer.tpl"}
</programlisting>
</example>
			<para>
			Both built-in functions and custom functions have the same syntax in
			the templates.
			</para>
		</sect2>
		<sect2>
			<title>Attributes</title>
			<para>
			Attributes to functions are much like HTML attributes. Static
			values don't have to be enclosed in quotes, but it is recommended
			for literal strings. If not quoted, you may use a syntax that Smarty may confuse
			with another function, such as a boolean value. Variables may
			also be used, and should not be in parenthesis.
			</para>
<example>
<title>Template example of function attribute syntax</title>
<programlisting>

{include file="header.tpl"}

{include file=$includeFile}

{include file=#includeFile#}

&lt;SELECT name=company&gt;
{html_options values=$vals selected=$selected output=$output}
&lt;/SELECT&gt;
</programlisting>
</example>
		</sect2>
		<sect2>
			<title>Comments</title>
			<para>
			Template comments are surrounded by asterisks, and that is surrounded
			by the delimiter tags like so: {* this is a comment *}
			Smarty comments are not displayed in the final output of the template.
			They are used mainly for making the templates more understandable.
			</para>		
<example>
<title>Template example of Comments</title>
<programlisting>

{* Smarty *}

{* include the header file here *}
{include file="header.tpl"}

{include file=$includeFile}

{include file=#includeFile#}

{* display dropdown lists *}
&lt;SELECT name=company&gt;
{html_options values=$vals selected=$selected output=$output}
&lt;/SELECT&gt;
</programlisting>
</example>
		</sect2>
	</sect1>
	<sect1 id="configfiles">
		<title>Config Files</title>
		<para>
		Config files are handy for designers to manage global
		template variables from one file. One example is template colors.
		Normally if you wanted to change the color scheme of an application,
		you would have to go through each and every template file
		and change the colors. With a config file, the colors can
		be kept in one place, and only one file needs to be updated.
        Note that to use config files, you must include the Config_File.class.php
		In your PHP include path. Config_File.class.php comes bundled with
		Smarty. Smarty will implicitly include the file if you
		don't already include it in your application.
		</para>
<example>
<title>Example of config file syntax</title>
<programlisting>

# global variables
pageTitle = "Main Menu"
bodyBgColor = #000000
tableBgColor = #000000
rowBgColor = #00ff00

[Customer]
pageTitle = "Customer Info"

[Login]
pageTitle = "Login"
focus = "username"
Intro = """This is a value that spans more
            than one line. you must enclose
			it in triple quotes."""
</programlisting>
</example>
			<para>
			Values of config file variables can be in qoutes, but not necessary.
			You can use either single or double quotes. If you have a value that
			spans more than one line, enclose the entire value with triple quotes
			("""). You can put comments into config files by any syntax that is
			not a valid config file syntax. We recommend using a hashmark (#) at the
			beginning of the line.
			</para>
			<para>
			This config file example has two sections. Section names are enclosed
			in brackets []. The four variables at the top are global
			variables, or variables not within a section. These variables are
			always loaded from the config file.
			If a particular section is loaded, then the global variables and the
			variables from that section are loaded. If a variable exists both as
			a global and in a section, the section variable is used. If you name two
			variables the same within a section, the last one will be used.
			</para>
			<para>
			Config files are loaded into templates with the built-in function
			called <link linkend="builtin.functions.configload">config_load</link>.
			</para>
	</sect1>
	<sect1 id="builtin.functions">
		<title>Built-in Functions</title>
		<para>
		Smarty comes with several built-in functions. Built-in functions
		are integral to the template language. You cannot create custom
		functions with the same names, nor can you modify built-in functions.
		</para>
		<sect2 id="builtin.functions.configload">
			<title>config_load</title>
			<para>
			This function is used for loading in variables from a
			configuration file into the template. You must have the Config_file.class.php
			file somewhere in your PHP include path for config_load to work properly.
			See <link linkend="configfiles">Config Files</link> for more info.
			</para>
<example>
<title>Template example of function config_load</title>
<programlisting>

{config_load file="colors.conf"}

&lt;html&gt;
&lt;title&gt;{#pageTitle#}&lt;/title&gt;
&lt;body bgcolor="{#bodyBgColor#}"&gt;
&lt;table border="{#tableBorderSize#}" bgcolor="{#tableBgColor#}"&gt;
	&lt;tr bgcolor="{#rowBgColor#}"&gt;
		&lt;td&gt;First&lt;/td&gt;
		&lt;td&gt;Last&lt;/td&gt;
		&lt;td&gt;Address&lt;/td&gt;
	&lt;/tr&gt;
&lt;/table&gt;
&lt;/body&gt;
&lt;/html&gt;
</programlisting>
</example>
			<para>
			Config files may also contain sections. You can load
			variables from within a section with the added attribute
			"section".
			</para>
<example>
<title>Template example of function config_load with section</title>
<programlisting>

{config_load file="colors.conf" section="Customer"}

&lt;html&gt;
&lt;title&gt;{#pageTitle#}&lt;/title&gt;
&lt;body bgcolor="{#bodyBgColor#}"&gt;
&lt;table border="{#tableBorderSize#}" bgcolor="{#tableBgColor#}"&gt;
	&lt;tr bgcolor="{#rowBgColor#}"&gt;
		&lt;td&gt;First&lt;/td&gt;
		&lt;td&gt;Last&lt;/td&gt;
		&lt;td&gt;Address&lt;/td&gt;
	&lt;/tr&gt;
&lt;/table&gt;
&lt;/body&gt;
&lt;/html&gt;
</programlisting>
</example>
		</sect2>
		<sect2>
			<title>include</title>
			<para>
			Include tags are used for including other templates into
			the current template. When a template is included, it
			inherits all the variables available to the current template.
			The include tag must have the attribute "file", which
			contains the path to the included template file relative
			to the template directory.
			</para>
<example>
<title>Template example of function include</title>
<programlisting>

{include file="header.tpl"}

{* body of template goes here *}

{include file="footer.tpl"}
</programlisting>
</example>
			<para>
			You can also pass variables to included templates as attributes.
			These will be passed to the template along with the current
			template variables. Attribute variables override template
			variables, in the case they are named alike. You can
			pass either static values or variables to included templates
			(although it doesn't make much sense to pass anything other than
			static values since variables are inherited anyways).
			</para>
<example>
<title>Template example of function include passing variables</title>
<programlisting>

{include file="header.tpl" title="Main Menu" table_bgcolor="#c0c0c0"}

{* body of template goes here *}

{include file="footer.tpl" logo="http://my.domain.com/logo.gif"}

</programlisting>
</example>
		</sect2>
		<sect2>
			<title>insert</title>
			<para>
			The insert tag in Smarty serves a special purpose. You may
			run into the situation where it is impossible to pass data to a template
			before the template is executed because there is info in the template
			needed to aquire the data, kind of a catch 22. The insert tag is a way
			to callback a function in PHP during runtime of the template. (This is much
			like the functionality of Server Side Includes in a static html page.)
			</para>
			<para>
			Let's say you have a template with a banner slot at the top of the page. The
			banner can contain any mixture of HTML, images, flash, etc. so we can't just
			use a static link here. In comes the insert tag: the template
			knows #banner_location_id# and #site_id# values (gathered from a config file),
			and needs to call a function to get the banner's contents.
			</para>
<example>
<title>Template example of function insert</title>
<programlisting>

{* example of fetching a banner *}
{insert name="getBanner" lid=#banner_location_id# sid=#site_id#}

</programlisting>
</example>
			<para>
			In this example, we are using the name "getBanner" and passing the
			parameters #banner_location_id# and #site_id#. Smarty will look
			for a function named insert_getBanner() in your PHP application, passing
			the values of #banner_location_id# and #site_id# as the first argument
			in an indexed array. All insert function names in
			your application must be prepended with "insert_" to remedy possible
			function name-space conflicts. Your insert_getBanner() function should
			do something with the passed values and return the results. These results
			are then displayed in the template in place of the insert tag.
			In this example, Smarty would call this function:
			insert_getBanner(array("banner_id" => "12345","page_id" => "67890"));
			and display the returned results in place of the insert tag.
			</para>
			<para>
			Another thing to keep in mind for the insert tag is caching. Smarty does not
			currently support caching but if that is eventually implemented, insert
			tags will not be cached. They will run dynamically every time the page
			is created. This works good for things like banners, polls, live weather,
			user feedback areas, etc.
			</para>
		</sect2>
		<sect2>
			<title>if,elseif,else</title>
			<para>
			if statements in Smarty have much the same flexability as php if statements,
			with a few added features for the template engine.
			Every if must be paired with /if. else and elseif are also permitted.
			"eq", "ne","neq", "gt", "lt", "lte", "le", "gte" "ge","is even","is odd",
			"is not even","is not odd","not","mod","div by","even by","odd by","==","!=",">",
			"<","<=",">=" are all valid conditional qualifiers.
			</para>
<example>
<title>Template example of if statements</title>
<programlisting>

{if $name eq "Fred"}
	Welcome Sir.
{elseif $name eq "Wilma"}
	Welcome Ma'am.
{else}
	Welcome, whatever you are.
{/if}

{* an example with "or" logic *}
{if $name eq "Fred" or $name eq "Wilma"}
	...
{/if}

{* parenthesis are allowed *}
{if ( $amount < 0 or $amount > 1000 ) and $volume >= #minVolAmt#}
	...
{/if}

{* you can also imbed php function calls *}
{if count($var) gt 0}
	...
{/if}

{* test if values are even or odd *}
{if $var is even}
	...
{/if}
{if $var is odd}
	...
{/if}
{if $var is not odd}
	...
{/if}

{* test if var is divisable by 4 *}
{if $var is div by 4}
	...
{/if}

{* same as previous example *}
{if $var is mod 4}
	...
{/if}

{* test if var is even, grouped by two. i.e.,
0=even, 1=even, 2=odd, 3=odd, 4=even, 5=even, etc. *}
{if $var is even by 2}
	...
{/if}

{* 0=even, 1=even, 2=even, 3=odd, 4=odd, 5=odd, etc. *}
{if $var is even by 3}
	...
{/if}

</programlisting>
</example>
		</sect2>
		<sect2>
			<title>ldelim,rdelim</title>
			<para>
			ldelim and rdelim are used for displaying the literal delimiter, in 
			our case "{" or "}". The template engine always tries to interpret
			delimiters, so this is the way around that.
			</para>
<example>
<title>Template example of ldelim, rdelim</title>
<programlisting>

{* this will print literal delimiters out of the template *}

{ldelim}funcname{rdelim} is how functions look in Smarty!


OUTPUT:

{funcname} is how functions look in Smarty!
</programlisting>
</example>
		</sect2>
		<sect2>
			<title>literal</title>
			<para>
			Literal tags allow a block of data to be taken literally,
			not being interpreted by the Smarty engine. This is handy
			for things like javascript sections, where there maybe
			curly braces and such things that would confuse the template
			parser. Anything within {literal}{/literal} tags is not
			interpreted, but displayed as-is.
			</para>
<example>
<title>Template example of literal tags</title>
<programlisting>

{literal}
	&lt;script language=javascript&gt;

        	&lt;!--
                	function isblank(field) {
                	if (field.value == '') 
                        	{ return false; }
                	else
                        	{
                        	document.loginform.submit();
                        	return true;
                        	}
                	}
        	// --&gt;

	&lt;/script&gt;
{/literal}
</programlisting>
</example>
		</sect2>
		<sect2 id="builtin.functions.section">
			<title>section,sectionelse</title>
			<para>
			Template sections are used for looping over arrays of data.
			All section tags must be paired with /section tags.
			Required parameters are "name" and "loop". The name of the
			section can be anything you like, made up of letters, numbers
			and underscores. Sections can be nested, and the nested
			section names must be unique from each other. The loop variable
			determines the number of times the section will loop.
			When printing a variable within a section, the section name
			must be prepended to the variable name, separated by a slash (/).
			sectionelse is executed when there are no values in the loop
			variable.
			</para>
<example>
<title>example: section</title>
<programlisting>


{* this example will print out all the values of the $custid array *}
{section name=customer loop=$custid}
	id: {$customer/custid}&lt;br&gt;
{/section}

OUTPUT:

id: 1000&lt;br&gt;
id: 1001&lt;br&gt;
id: 1002&lt;br&gt;

</programlisting>
</example>

<example>
<title>example: section loop variable</title>
<programlisting>

{* the loop variable only determines the number of times to loop.
   you can access any variable from the template within the section.
   This example assumes that $custid, $name and $address are all
   arrays containing the same number of values *}
{section name=customer loop=$custid}
	id: {$customer/custid}&lt;br&gt;
	name: {$customer/name}&lt;br&gt;
	address: {$customer/address}&lt;br&gt;
	&lt;p&gt;
{/section}


OUTPUT:

id: 1000&lt;br&gt;
name: John Smith&lt;br&gt;
address: 253 N 45th
&lt;p&gt;
id: 1001&lt;br&gt;
name: Jack Jones&lt;br&gt;
address: 417 Mulberry ln
&lt;p&gt;
id: 1002&lt;br&gt;
name: Jane Munson
address: 5605 apple st
&lt;p&gt;

</programlisting>
</example>

<example>
<title>example: section names</title>
<programlisting>

{* the name of the section can be anything you like,
   and it is used to reference the data within the section *}
{section name=mydata loop=$custid}
	id: {$mydata/custid}&lt;br&gt;
	name: {$mydata/name}&lt;br&gt;
	address: {$mydata/address}&lt;br&gt;
	&lt;p&gt;
{/section}

</programlisting>
</example>

<example>
<title>example: nested sections</title>
<programlisting>

{* sections can be nested as deep as you like. With nested sections,
   you can access complex data structures, such as multi-dimensional
   arrays. In this example, $customer/contact_type is an array of
   contact types for the current customer. *}
{section name=customer loop=$custid}
	id: {$customer/custid}&lt;br&gt;
	name: {$customer/name}&lt;br&gt;
	address: {$customer/address}&lt;br&gt;
	{section name=contact loop=$customer/contact_type}
		{$customer/contact/contact_type}: {$customer/contact/contact_info}&lt;br&gt;
	{/section}
	&lt;p&gt;
{/section}


OUTPUT:

id: 1000&lt;br&gt;
name: John Smith&lt;br&gt;
address: 253 N 45th
home phone: 555-555-5555
cell phone: 555-555-5555
e-mail: john@mydomain.com
&lt;p&gt;
id: 1001&lt;br&gt;
name: Jack Jones&lt;br&gt;
address: 417 Mulberry ln
home phone: 555-555-5555
cell phone: 555-555-5555
e-mail: jack@mydomain.com
&lt;p&gt;
id: 1002&lt;br&gt;
name: Jane Munson
address: 5605 apple st
home phone: 555-555-5555
cell phone: 555-555-5555
e-mail: jane@mydomain.com
&lt;p&gt;


</programlisting>
</example>

<example>
<title>example: sectionelse</title>
<programlisting>

{* sectionelse will execute in the case there are no $custid values *}
{section name=customer loop=$custid}
	id: {$customer/custid}&lt;br&gt;
{sectionelse}
	there are no values in $custid.
{/section}

</programlisting>
</example>
		<para>
		Sections also have their own variables that handle section properties.
		These are indicated by percent signs around the variable name, like so:
		%sectionname.varname%
		</para>
			<sect3>	
			<title>index</title>
			<para>
			index is used to display the current loop iteration,
			starting with zero.
			</para>
<example>
<title>example: section property index</title>
<programlisting>
{section name=customer loop=$custid}
	{%customer.index%} id: {$customer/custid}&lt;br&gt;
{/section}


OUTPUT:

0 id: 1000&lt;br&gt;
1 id: 1001&lt;br&gt;
2 id: 1002&lt;br&gt;

</programlisting>
</example>
			</sect3>
			<sect3>	
			<title>rownum</title>
			<para>
			rownum is used to display the current loop iteration,
			starting with one.
			</para>
<example>
<title>example: section property rownum</title>
<programlisting>
{section name=customer loop=$custid}
	{%customer.rownum%} id: {$customer/custid}&lt;br&gt;
{/section}


OUTPUT:

1 id: 1000&lt;br&gt;
2 id: 1001&lt;br&gt;
3 id: 1002&lt;br&gt;

</programlisting>
</example>
			</sect3>
			<sect3>	
			<title>loop</title>
			<para>
			loop is used to display the total number
			of iterations this section is looped. This can be used
			inside or after the section.
			</para>
<example>
<title>example: section property index</title>
<programlisting>
{section name=customer loop=$custid}
	{%customer.index%} id: {$customer/custid}&lt;br&gt;
{/section}

There were {%customer.loop%} customers shown above.

OUTPUT:

0 id: 1000&lt;br&gt;
1 id: 1001&lt;br&gt;
2 id: 1002&lt;br&gt;

There were 3 customers shown above.

</programlisting>
</example>
			</sect3>
			<sect3>	
			<title>show</title>
			<para>
			show is used both as a parameter to section,
			as well as displaying its value. show is a
			boolean value, true or false. If false, the
			section will not be displayed. If there is a
			sectionelse present, that will be alternately
			displayed.
			</para>
<example>
<title>example: section property rownum</title>
<programlisting>
{* $show_customer_info may have been passed from the PHP
   application, to regulate whether or not this section shows *}
{section name=customer loop=$custid show=$show_customer_info}
	{%customer.rownum%} id: {$customer/custid}&lt;br&gt;
{/section}

{if %customer.show%}
	the section was shown.
{else}
	the section was not shown.
{/if}


OUTPUT:

1 id: 1000&lt;br&gt;
2 id: 1001&lt;br&gt;
3 id: 1002&lt;br&gt;

the section was shown.

</programlisting>
</example>
			</sect3>
		</sect2>
		<sect2>
			<title>strip</title>
			<para>
			Many times web designers
			run into the issue where white space and carriage returns
			affect the output of the rendered HTML (browser "features"), so you
			must run all your tags together in the template to get the
			desired results. This usually ends up in unreadable or
			unmanagable templates.
			</para>
			<para>
			Anything within {strip}{/strip} tags in Smarty are stripped of
			the extra spaces or carriage returns at the beginnings and
			ends of the lines before they are displayed.
			This way you can keep your templates readable, and not worry
			about extra white space causing problems.
			</para>
<example>
<title>Template example of strip tags</title>
<programlisting>

{* the following will be all run into one line upon output *}
{strip}
&lt;table border=0&gt;
	&lt;tr&gt;
		&lt;td&gt;
			&lt;A HREF="{$url}"&gt;
			&lt;font color="red"&gt;This is a test&lt;/font&gt;
			&lt;/A&gt;
		&lt;/td&gt;
	&lt;/tr&gt;
&lt;/table&gt;
{/strip}


OUTPUT:

&lt;table border=0&gt;&lt;tr&gt;&lt;td&gt;&lt;A HREF="http://my.domain.com"&gt;&lt;font color="red"&gt;This is a test&lt;/font&gt;&lt;/A&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

</programlisting>
</example>
		<para>
		Notice that in the above example, all the lines begin and end
		with HTML tags. Be aware that all the lines are run together.
		If you have plain text at the beginning or end of any line,
		they will be run together, and may not be desired results.
		</para>
		</sect2>
	</sect1>
	<sect1 id="custom.functions">
		<title>Custom Functions</title>
		<para>
		Custom functions in Smarty work much the same as the built-in functions
		syntactically. Two custom functions come bundled with Smarty. You can
		also write your own.
		</para>
		<sect2>
			<title>html_options</title>
			<para>
			html_options is a custom function that creates html option
			lists with provided data. It takes care of which item is
			selected by default as well.
			</para>
<example>
<title>Template example of html_options</title>
<programlisting>

{* assume that $cust_ids, and $cust_names are arrays of values,
	and $customer_id may or may not be set to a value *}

&lt;select name=customer_id&gt;
	{html_options values=$cust_ids selected=$customer_id output=$cust_names}
&lt;/select&gt;


OUTPUT:

&lt;select name=customer_id&gt;
	&lt;option value="1000">Joe Schmoe&lt;option&gt;
	&lt;option value="1001" selected>Jack Smith&lt;option&gt;
	&lt;option value="1002">Jane Johnson&lt;option&gt;
	&lt;option value="1003">Charlie Brown&lt;option&gt;
&lt;/select&gt;

</programlisting>
</example>
			<para>
			This will create an option dropdown list using the values
			of the variables supplied in the template.
			</para>
		</sect2>
		<sect2>
			<title>html_select_date</title>
			<para>
			html_select_date is a custom function that creates date dropdowns
			for you. It can display any or all of year, month, and day. Possible
			attributes are (attr name, type, default val):
			</para>
			<itemizedlist>
				<listitem><para>prefix,string,"Date_"</para></listitem>
				<listitem><para>time,timestamp,(current time)</para></listitem>
				<listitem><para>start_year,int,(current year)</para></listitem>
				<listitem><para>end_year	int (same as start_year)</para></listitem>
				<listitem><para>display_days, boolean, true</para></listitem>
				<listitem><para>display_months, boolean, true</para></listitem>
				<listitem><para>display_years, boolean, true</para></listitem>
				<listitem><para>month_format, strftime, "%B"</para></listitem>
				<listitem><para>day_format, strftime, "%02d"</para></listitem>
				<listitem><para>year_as_text, boolean, true</para></listitem>
			</itemizedlist>
<example>
<title>Template example of html_select_date</title>
<programlisting>

{html_select_date}


OUTPUT:

&lt;select name="Date_Month"&gt;
&lt;option value="1"&gt;January&lt;/option&gt;
&lt;option value="2"&gt;February&lt;/option&gt;
&lt;option value="3"&gt;March&lt;/option&gt;
&lt;option value="4"&gt;April&lt;/option&gt;
&lt;option value="5"&gt;May&lt;/option&gt;
&lt;option value="6"&gt;June&lt;/option&gt;
&lt;option value="7"&gt;July&lt;/option&gt;
&lt;option value="8"&gt;August&lt;/option&gt;
&lt;option value="9"&gt;September&lt;/option&gt;
&lt;option value="10"&gt;October&lt;/option&gt;
&lt;option value="11"&gt;November&lt;/option&gt;
&lt;option value="12" selected&gt;December&lt;/option&gt;
&lt;/select&gt;
&lt;select name="Date_Day"&gt;
&lt;option value="1"&gt;01&lt;/option&gt;
&lt;option value="2"&gt;02&lt;/option&gt;
&lt;option value="3"&gt;03&lt;/option&gt;
&lt;option value="4"&gt;04&lt;/option&gt;
&lt;option value="5"&gt;05&lt;/option&gt;
&lt;option value="6"&gt;06&lt;/option&gt;
&lt;option value="7"&gt;07&lt;/option&gt;
&lt;option value="8"&gt;08&lt;/option&gt;
&lt;option value="9"&gt;09&lt;/option&gt;
&lt;option value="10"&gt;10&lt;/option&gt;
&lt;option value="11"&gt;11&lt;/option&gt;
&lt;option value="12"&gt;12&lt;/option&gt;
&lt;option value="13" selected&gt;13&lt;/option&gt;
&lt;option value="14"&gt;14&lt;/option&gt;
&lt;option value="15"&gt;15&lt;/option&gt;
&lt;option value="16"&gt;16&lt;/option&gt;
&lt;option value="17"&gt;17&lt;/option&gt;
&lt;option value="18"&gt;18&lt;/option&gt;
&lt;option value="19"&gt;19&lt;/option&gt;
&lt;option value="20"&gt;20&lt;/option&gt;
&lt;option value="21"&gt;21&lt;/option&gt;
&lt;option value="22"&gt;22&lt;/option&gt;
&lt;option value="23"&gt;23&lt;/option&gt;
&lt;option value="24"&gt;24&lt;/option&gt;
&lt;option value="25"&gt;25&lt;/option&gt;
&lt;option value="26"&gt;26&lt;/option&gt;
&lt;option value="27"&gt;27&lt;/option&gt;
&lt;option value="28"&gt;28&lt;/option&gt;
&lt;option value="29"&gt;29&lt;/option&gt;
&lt;option value="30"&gt;30&lt;/option&gt;
&lt;option value="31"&gt;31&lt;/option&gt;
&lt;/select&gt;
&lt;select name="Date_Year"&gt;
&lt;option value="2001" selected&gt;2001&lt;/option&gt;
&lt;/select&gt;

</programlisting>
</example>


<example>
<title>Template example of html_select_date</title>
<programlisting>


{html_select_date prefix="StartDate" time=$time start_year=1995 end_year=2001 display_days=false}

&lt;select name="StartDateMonth"&gt;
&lt;option value="1"&gt;January&lt;/option&gt;
&lt;option value="2"&gt;February&lt;/option&gt;
&lt;option value="3"&gt;March&lt;/option&gt;
&lt;option value="4"&gt;April&lt;/option&gt;
&lt;option value="5"&gt;May&lt;/option&gt;
&lt;option value="6"&gt;June&lt;/option&gt;
&lt;option value="7"&gt;July&lt;/option&gt;
&lt;option value="8"&gt;August&lt;/option&gt;
&lt;option value="9"&gt;September&lt;/option&gt;
&lt;option value="10"&gt;October&lt;/option&gt;
&lt;option value="11"&gt;November&lt;/option&gt;
&lt;option value="12" selected&gt;December&lt;/option&gt;
&lt;/select&gt;
&lt;select name="StartDateYear"&gt;
&lt;option value="1999"&gt;1995&lt;/option&gt;
&lt;option value="1999"&gt;1996&lt;/option&gt;
&lt;option value="1999"&gt;1997&lt;/option&gt;
&lt;option value="1999"&gt;1998&lt;/option&gt;
&lt;option value="1999"&gt;1999&lt;/option&gt;
&lt;option value="2000" selected&gt;2000&lt;/option&gt;
&lt;option value="2001"&gt;2001&lt;/option&gt;
&lt;/select&gt;

</programlisting>
</example>
		</sect2>
		<sect2>
			<title>Creating your own Custom Functions</title>
			<para>
			Creating your own functions is a fairly straight forward process.
			The best way is to look at the ones that come with Smarty as
			examples. The function names begin with smarty_func_ and they are
			located in the Smarty.addons.php file.
			</para>
			<itemizedlist>
				<listitem><para>add your function to the Smarty.addons.php file.
						It is recommended that you prepend your function name
						with smarty_func_</para></listitem>
				<listitem><para>map a template function name to your PHP function.
							This is done at the top of the Smarty.class.php file
							in the $custom_funcs array.</para></listitem>
				<listitem><para>Thats it! you can now call that function
					from within Smarty.</para></listitem>
			</itemizedlist>			
			<para>
			All attributes passed to custom functions are passed into the
			first argument as an indexed array. One way to get to those
			values is to call extract(func_get_arg(0)); at the top of your
			function. Anything that the function returns gets displayed
			in place of the tag in the template.
			</para>
		</sect2>
	</sect1>
	<sect1 id="variable.modifiers">
		<title>Variable Modifiers</title>
		<para>
		Variable modifiers are a bit different than
		<link linkend="custom.functions">custom functions</link>.
		They do just what they sound like, they modify variables before
		they are displayed to the template. The best way to explain
		these are by example.
		</para>
<example>
<title>Template example of variable modifiers</title>
<programlisting>

{* this displays a variable, unmodified *}
{$articleTitle}

OUTPUT:

Burger King fire leaves seven pregnant teenagers &lt;jobless&gt;


{* this displays the variable in all upper case *}
{$articleTitle|upper}

OUTPUT:

BURGER KING FIRE LEAVES SEVEN PREGNANT TEENAGERS &lt;JOBLESS&gt;


{* this displays the variable html escaped *}
{$articleTitle|escape}

OUTPUT:

Burger King fire leaves seven pregnant teenagers &amp;lt;jobless&amp;gt;


{* this displays the variable uppercased AND html escaped *}
{$articleTitle|upper|escape}

OUTPUT:

BURGER KING FIRE LEAVES SEVEN PREGNANT TEENAGERS &amp;lt;JOBLESS&amp;gt;


{* an example of passing a parameter to a modifier:
	this displays the variable url escaped *}
{$articleTitle|escape:"url"}

OUTPUT:

Burger+King+fire+leaves+seven+pregnant+teenagers+%3Cjobless%3e


{* print the first 24 characters of this variable, and
	follow with ... if it was longer *}
{$articleTitle|truncate:24:"..."}

OUTPUT:

Burger King fire...


{* print the date in default format *}
{$startTime|date_format}

OUTPUT:

Dec 13, 2000


{* print the hour, minute and second portion of a date *}
{$startTime|date_format:"%h:%m:%s"}

OUTPUT:

10:33:02

{* print a number to the first two decimals *}
{$amount|string_format:"%.2f"}

OUTPUT:

24.02

{* print "Home Page" if $title is empty *}
{$title|default:"Home Page"}

OUTPUT:

Home Page


</programlisting>
</example>
		<para>
		All modifiers will get the value of the variable as the first argument,
		and must return a single value. Modifier parameters are separated by colons.
		Any additional parameters passed to a modifier are passed as-is positionally,
		much like calling a PHP function. You can also use native
		PHP functions as modifiers, but only if they expect the correct
		arguments. If they do not, you can always write a wrapper function
		in Smarty to get what you want (date_format is a wrapper function
		to strftime() for example.) You can chain as many modifiers
		together on a variable as you like, separating each with a vertical
		pipe "|".
		</para>
		<para>
		NOTE: if you apply a modifier to an array
		instead of a single value variable, the modifier will be applied to every
		value in that array. If you really want the entire array passed
		to the modifier, you must prepend it with an "@" sign like so:
		{$articleTitle|@count} (this will print out the number of elements
		in the $articleTitle array.)
		</para>
		<sect2>
			<title>captialize</title>
			<para>
			This is used to capitalize the first letter of all words in a variable.
			</para>
		</sect2>
		<sect2>
			<title>date_format</title>
			<para>
			This formats a date into the given strftime() format. All dates
			should be passed to Smarty as a timestamp so that the template
			designer has full control of how this date is formatted. The
			default format is "%b %e, %Y", or "Jan 4, 2001" for example.
			These are the possible conversion specifiers:
			</para>
<example>
<title>date_format conversion specifiers</title>
<programlisting>
%a - abbreviated weekday name according to the current locale 

%A - full weekday name according to the current locale 

%b - abbreviated month name according to the current locale 

%B - full month name according to the current locale 

%c - preferred date and time representation for the current locale 

%C - century number (the year divided by 100 and truncated to an integer, range 00 to 99) 

%d - day of the month as a decimal number (range 00 to 31) 

%D - same as %m/%d/%y 

%e - day of the month as a decimal number, a single digit is preceded by a space (range ' 1' to '31') 

%h - same as %b 

%H - hour as a decimal number using a 24-hour clock (range 00 to 23) 

%I - hour as a decimal number using a 12-hour clock (range 01 to 12) 

%j - day of the year as a decimal number (range 001 to 366) 

%m - month as a decimal number (range 01 to 12) 

%M - minute as a decimal number 

%n - newline character 

%p - either `am' or `pm' according to the given time value, or the corresponding strings for the current locale 

%r - time in a.m. and p.m. notation 

%R - time in 24 hour notation 

%S - second as a decimal number 

%t - tab character 

%T - current time, equal to %H:%M:%S 

%u - weekday as a decimal number [1,7], with 1 representing Monday 

%U - week number of the current year as a decimal number, starting with the first Sunday as the first day of the first week 

%V - The ISO 8601:1988 week number of the current year as a decimal number, range 01 to 53, where week 1
is the first week that has at least 4 days in the current year, and with Monday as the first day of the week. 

%W - week number of the current year as a decimal number, starting with the first Monday as the first day of the first week 

%w - day of the week as a decimal, Sunday being 0 

%x - preferred date representation for the current locale without the time 

%X - preferred time representation for the current locale without the date 

%y - year as a decimal number without a century (range 00 to 99) 

%Y - year as a decimal number including the century 

%Z - time zone or name or abbreviation 

%% - a literal `%' character 
</programlisting>
</example>

		</sect2>
		<sect2>
			<title>default</title>
			<para>
			This is used to set a default value for a variable. If the variable
			is empty or unset, the given default value is printed instead.
			Default takes one argument, the value to use as the default value.
			</para>
		</sect2>
		<sect2>
			<title>escape</title>
			<para>
			This is used to html or url escape a variable. By default,
			the variable is html escaped. possible arguments are "url" or "html".
			</para>
		</sect2>
		<sect2>
			<title>lower</title>
			<para>
			This is used to lowercase a variable.
			</para>
		</sect2>
		<sect2>
			<title>replace</title>
			<para>
			A simple search and replace on a variable. The first argument is
			what to search for, the second argument is what to replace it with.
			</para>
		</sect2>
		<sect2>
			<title>spacify</title>
			<para>
			spacify is a way to insert spaces between every character of a variable.
			You can optionally pass a different character (or string) to insert.
			</para>
		</sect2>
		<sect2>
			<title>string_format</title>
			<para>
			This is a way to format strings, such as decimal numbers and such.
			Use the syntax for sprintf for the formatting.
			</para>
		</sect2>
		<sect2>
			<title>strip_tags</title>
			<para>
			This strips out markup tags, basically anything between &lt; and &gt;.
			</para>
		</sect2>
		<sect2>
			<title>truncate</title>
			<para>
			This truncates a variable to a character length, default is 80. As
			an optional second parameter, you can specify a string of text
			to display at the end if the variable was truncated. The
			characters in the string are included with the original truncation length.
			By default, truncate will attempt to cut off at a word boundary. If
			you want to cut off at the exact character length, pass the optional
			third parameter of true.
			</para>
		</sect2>
		<sect2>
			<title>upper</title>
			<para>
			This is used to uppercase a variable.
			</para>
		</sect2>
		<sect2>
			<title>Creating your own Variable Modifiers</title>
			<para>
			Creating your own modifiers is a fairly straight forward process.
			The best way is to look at the ones that come with Smarty as
			examples. The function names begin with smarty_mod_ and they are
			located in the Smarty.addons.php file.
			</para>
			<itemizedlist>
				<listitem><para>add your modifier to the Smarty.addons.php file.
						It is recommended that you prepend your function name
						with smarty_mod_</para></listitem>
				<listitem><para>map a template modifier name to your PHP function.
							This is done at the top of the Smarty.class.php file
							in the $custom_mods array.</para></listitem>
				<listitem><para>Thats it! you can now use that modifier
					from within Smarty.</para></listitem>
			</itemizedlist>			
		</sect2>
	</sect1>	
</chapter>
<chapter>
	<title>Troubleshooting</title>
	<para></para>
	<sect1>
		<title>Smarty/PHP errors</title>
		<para>
		As of now, Smarty is not a validating template parser. This means that
		the parser will blindly convert the template to PHP scripts, irregardless
		of any syntax errors in the markup tags that may be present in the template.
		Smarty can catch certain template errors like missing attributes to
		functions, but not syntax errors like missing close tags.
		These types of errors can end up in PHP run-time errors.
		When you encounter a PHP error when attempting to display the
		template in a browser, the error line number will correspond to the
		compiled PHP template, not the template itself. This may be a bit confusing
		or for the template designer. Our experience is to tell the
		designers to check their work often, and ask the programmers for help
		if they are really stuck. Usually you can look at the template and spot the
		syntax error. Maybe you left a delimeter off, or you didn't properly close
		an {if}{/if} or {section}{/section} tag. If you can't find it, you must open
		the compiled PHP file and go to the line number to figure out what went wrong.
		</para>
	</sect1>
</chapter>
<chapter id="bugs">
	<title>BUGS</title>
	<para>
    There are no known bugs with Smarty, although there are some
    bugs in PHP that can cause problems with Smarty. preg_grep() previous
    to 4.0.4 has a bug which Smarty accomodates with a built-in workaround.
    PHP 4.0.4 has a bug with user callbacks which would cause this
    syntax in Smarty to crash PHP: {$varname|@modname}
    Use PHP 4.0.4pl1 to fix this, or avoid using the "@" with
    <link linkend="variable.modifiers">modifiers</link>.	
	</para>
</chapter>
</book>