5
           
            
                
     
    
    I found something. 
XOOPS Documentation Roadmap, by Horacio Salazar, in "Documents for developers and power users" section:
Quote:
 NOTICE: For this particular area this is a proposal to the developers. The more technical documents would be under the devs’ direct control, as asked by the devs themselves. This is an area I don’t know much about, so this is mainly a kind of wish list. Please be aware that these lists include both long and short documents. Some of the documents proposed here are only a few paragraphs long, while others are booklets or complete handbooks.
...
Technical documents
 *(XD-101) XOOPS Core Functions
 *(XD-102) XOOPS Base Documents - phpDocs
 *(XD-103) XOOPS Base Documents - phpXRef
 *(XD-104) XOOPS API
 *(XD-104) XOOPS Javascript Functions 
...
and "Documents for general users" area:
Quote:
Assorted subjects
 *(XU-201) The XOOPS Module Registry
 *(XU-202) The XOOPS Theme Registry
 *(XU-203) XOOPS Hacks
 *(XU-204) An introduction to XOOPS and Smarty
 *(XU-205) The XOOPS Glossary
 *(XU-206) Best of XOOPS' Forums
 *(XU-207) An assortment of XOOPS FAQs
 *(XU-208) Favorite Code Snippets 
Is this just a proposal or it was done?