Title	:	suPerlative: The ht Preprocessor
Author	:	ALR
Abstract:
	<b>ht</b> is a <em>pre-processor</em> for HTML.
It facilitates the maintenance of a large site by abstracting
out common 'boilerplate' segments of code, e.g. header and
footer segments that are similar system-wide. A number of
varying styles and macros can also be supported.
+++
Content	:
Central to our operations is 'ht', which takes a simplified
HTML file and adds 'boilerplate' stuff such as banner ads
and navigation menus. ht files start with a header 
<a href="HT.ht">such as</a>:-
<xmp>
Title	:	suPerlative: The ht Preprocessor
Author	:	ALR
Abstract:
	<b>ht</b> is a <em>pre-processor</em> for HTML.
It facilitates the maintenance of a large site by abstracting
out common 'boilerplate' segments of code, e.g. header and
footer segments that are similar system-wide. A number of
varying styles and macros can also be supported.
+++
Content	:
Central to our operations is 'ht', which takes a simplified
HTML file and adds 'boilerplate' stuff such as banner ads
and navigation menus. ht files start with a header 
<a href="HT.ht">such as</a>:-
</xmp>
	It's wired with several standard conventions, such as author
	abbreviations ('AR' for 'Alan Richmond') and table macros, and with styles.

	There is a <a href="ht">main program</a> and several 
	<a href="ht_subs.pl">subroutines</a>, e.g. <code>Head</code>
	and <code>Foot</code>, which are also used by most of our other scripts.
<p>
	The benefits of using ht are:-
<ul>
<li>	Helps enforce consistency and uniform style.
<li>	Writes valid <a href="/Authoring/HTML/4/">HTML 4</a>
	code for the boilerplate.
<li>	Enables abbreviation of common constructs, saving time.
<li>	Facilitates site moves, as when we moved to the 
	<a href="http://www.Internet.com/">Internet.com</a> servers - 
	took much less than a day, which surprised the new owners..
<li>	Facilitates global changes, e.g copyright year, navigation menus, etc.
<li>	Figures out where it is, so that navigation uplinks can be appended.
</ul>
	I believe most people think you only have two choices for creating HTML
	- use an editor or code by hand.
	But there's a third one which works very well for us:
	we use a (home-grown) preprocessor. If you like it's a variant of the
	template method; we have a number of styles built in and can modify them
	with some parameters.
	<b><a href="ht.html">ht</a></b>
	is a <a href="/Authoring/Languages/Perl/">Perl</a>
	preprocessor that I wrote for maintaining The WDVL. It
	allows me to write HTML without having to put on all the 'boilerplate'.
<p>
	ht generates all the header, table and footer HTML... Using a
	preprocessor such as ht provides much more flexibility than typical
	<a href="/Vlib/Authoring/HTML_Editors.html">HTML editors</a>
	(which anyway tend to generate bloated and unreadable code)
	- for example I can easily change the site style by changing ht and
	running source files through it..  (very powerful when combined with
	<a href="/Authoring/Style/Sheets/">style sheets</a>).
<p>
	An <a href="ht.ht">ht file looks like this</a>.
<p>
	You run the file through 'ht' and it sticks on the boilerplate,
	modified if necessary according to the header parameters and with any
	macros (abbreviations) expanded.
	This makes it very easy to create HTML in one of our
	standard styles, but you can also control
	the end result
	as much as you want
	since the input can contain HTML. And it's also very useful for
	our mirrors, e.g. there can be small differences automatically
	introduced such as crediting the host or pointing to CGI programs on the
	primary site because we don't have CGI access on every mirror.
	With 1,500 pages to maintain this would hard to do with an editor..
<p>
	We don't currently use a database but a logical extension of this
	method would be to put the ht files into a database
	and then we could generate
	the pages dynamically, e.g. to account for browser differences.

	This approach isn't for everyone but anyone who wallows in Perl and
	HTML should love it.. 
<p>
	Finally - ht also allows a small set of abbreviations; e.g.
<xmp>
<center>
	@Prev(Why.html)
	@Up(index.html)
	@Next(Stats.html)
</center>
</xmp>
	creates the following links:-
<p>
<center>
	@Prev(Why.html)
	@Up(index.html)
	@Next(Stats.html)
</center>
<p>
	To use ht, you need:
<ul>
<li>	<a href="ht">ht main program</a>
<li>	<a href="ht_subs.pl">ht subroutines</a>
<li>	<a href="site.pl">site.pl</a> for customization.
<li>	<a href="ht.html">ht documentation</a>
</ul>
	You would certainly need to edit the subroutines file to change or remove things like the list of author initials, and the navigation menus.