Adding attributes/parameters to the "<para>" template?

Hi,
  
 
  
I am having a hard time trying add a "para template" in my "customization" layer.
  
I would want to add an parameter to the para template.  This parameter would
  
contain a string that would be prepended to the paragraph. 
  
 
  
So if I had in my xml file this ...
  
 
  
<para pm="+++ ">Hi there </para>
  
 
  
... output would be in html something like
 ...
  
 
  
<p>+++ Hi there</p>
  
 
  
Also how would I make the template use a default value if the attribute/parameter
  
was left out?  Also how could I make another template say ... strict_para ... that
  
would cause an error if the parameter was left out?
  
 
  
I guess I should get a book on xsl ... right?  or is xstl?
  
 
  
Thanks
 
 
Plankton
  
 
  
 

		 
 
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