Hi Vyzo, Carl, and Grant - after struggling with this some more, I was finally able to create a macro with multiple definitions.  Below are my take-aways: <ul><li>use with-syntax over let: let allows me to create my own symbol transformations in a function - with-syntax allows the same in a macro </li><li>symbol != syntax-object: at first my transform function returns a symbol and I couldn't create a definition - it doesn't work until I figure out I need a syntax-object and how to use datum->syntax-object to do so </li><li>The way to manipulate symbol is still through string-append - this means I need to convert the type from syntax-object -> symbol -> string -> symbol -> syntax-object... seems quite a bit of work ;) </li><li>use define-for-syntax rather than define to abstract the transformation </li><li>syntax-case affords more control... syntax-rules use might be limited </li></ul>My head still hurts but I definitely learned something here - again thanks for the help! ;) yinso <div> On 4/13/07, Dimitris Vyzovitis <<a href="mailto:vyzo@media.mit.edu">vyzo@media.mit.edu</a>> wrote:<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> On Fri, 13 Apr 2007, Yin-So Chen wrote: > Hi all - > > I have a couple of related questions about define-syntax - basically I am > wondering how some language facilities such as struct or classes are done as > macros: > >    1. how can define-syntax create multiple forms/definitions - I found >    the entry on <a href="http://community.schemewiki.org/?scheme-faq-macros">http://community.schemewiki.org/?scheme-faq-macros </a> but >    unable to extrapolate from there to creating of something similar to a >    define-struct >    2. how to generate names based on the struct/class name into the >    definitions - seems like there needs to be ways of inserting results of a >    function call into define-syntax? If you are trying to make a define-struct like macro with standard naming conventions, check generate-struct-declaration (lives in struct.ss of the syntax collection). For more general, arbitrary symbol injections, syntax-object->datum and dautm->syntax-object are your friends. Break down the syntax with syntax-case, ->datum, manipulate to make your identifiers, ->syntax. To put the result of function calls in the transformer environment back into generated syntax, use quasisyntax/unsyntax/unsyntax-splicing (#` #, #,@) -- vyzo </blockquote></div> -- <a href="http://www.yinsochen.com">http://www.yinsochen.com</a> ...continuous learning...