---
title: Plugins, Helpers and Extensions      
filter:
  - erb
  - textileplus
---

h1. <%= @page.title %>

<div class="toc">

p(toc-title). Contents:
   
* "Using Embedded Ruby (ERB) Helpers in Your Slides":#lib
* "Built-In Helpers":#builtin
* "Code/Syntax Highlighting Helpers":#code
* "Questions? Comments?":#questions

</div>




h2(#lib). Using Embedded Ruby (ERB) Helpers in Your Slides

Slide Show (S9) includes support for plugins and helpers
and lets you use Embedded Ruby (ERB) in your slide source. Example:

{{{
h1. Today's Date 
<%%= Time.now %> 
}}}

If you want to use your own helpers put your code in the @./lib@ 
folder (or any subfolders) and your code gets loaded on startup. 

h2(#builtin). Built-In Helpers

* @include@     -  Lets you include text. Example:

{{{
<%%= include 'help.txt' %>
}}}

* @content_for@  - Lets you add content to your templates from your source a la Rails.

In your slide source use: 
  
{{{
<%% content_for :head do %> 
  your content here e.g. more meta tags; javascript includes etc. 
<%% end %> 
}}}

In your template use: 

{{{
<%%= content_for :head %>
}}}

and it will include the marked content from your source.
Note, you can use @:foo@, @:bar@ or whatever key you 
want instead of @:head@ and also note a la Rails you can use the same 
key as many times as you want. The new content just gets added. 

h2(#code). Code/Syntax Highlighting Helpers

The @code@ helper lets you include and syntax highlight code e.g.

{{{
<%% code do %> 
  your inline code here 
<%% end %> 
}}}

or include code: 

{{{
<%%= code 'highlight.rb' %> 
}}}

To select the language (default is @ruby@) use the @:lang@ option e.g.

{{{
<%%= code 'effects.css', lang: => 'css' %> 
}}}

Note, you can also include parts of files using "Codex-style markers":http://pragdave.blogs.pragprog.com/pragdave/2008/05/our-take-on-pre.html  
in your source (e.g. @#START:your_marker_here@ and 
@#END:your_marker_here@) and you can also pass along an extra CSS class 
(@large@,@small@,@tiny@,etc.) e.g. this directive in Codex

{{{
:code code/meta/my_ostruct.rb[impl class=code-small] 
}}}

becomes in S9: 

{{{
<%%= code 'code/meta/my_ostruct.rb#impl', class:=>'small' %> 
}}}

To select the underlying engine for code highlighting use the @:engine@ option e.g.

{{{
<%%= code 'highlight.rb', :engine => 'coderay' %> 
}}}

or use a header to set it once e.g:

{{{
code-engine: uv   # or use your very own code engine here 
}}}

You can also use the built-in code highlighting engines 
"stand-alone" without the code "wrapper" helper. 
To use Ultraviolet use: 

{{{
<%% uv do %> 
  your inline code here 
<%% end %> 
}}}

To use CodeRay use: 

{{{
<%% coderay do %> 
  your inline code here 
<%% end %> 
}}} 
   
Note, that @uv@ and @coderay@ only support inline code (if you want to 
include code use a nested include e.g.: 

{{{
<%% coderay :lang => 'css', :line_numbers => 'off' do %> 
  <%%= include 'effects.css' %> 
<%% end %> 
}}}

For more options or on how to write your own syntax highlighting 
helpers it might be best to check the "source of the helpers":http://github.com/geraldb/slideshow/tree/master/code/lib/slideshow/helpers.

h2(#questions). Questions? Comments?

Questions? Comments? Send them along to the
"Free Web Slide Show Alternatives (S5, S6, S9, Slidy And Friends) Forum/Mailing List":http://groups.google.com/group/webslideshow.
Thanks!