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Functions with private context
It is possible to define a private context around a function
(define function-with-private-context
 (let (CONTEXT)
   (lambda (PARAMETERS)
      BODY)))
Expression

 Value

(define document
 (let
   ((html 
     (xml-modify-element html 
      'xmlns "http://www.w3.org/1999/xhtml"))
    (body 
     (xml-modify-element body 
      'bgcolor (rgb-color-encoding 255 0 0)))
      )
   (lambda (ttl bdy)
    (html
      (head (title ttl))
      (body bdy)))))
 
 
(document "A title" "A body")
 
<html xmlns = 
       "http://www.w3.org/1999/xhtml">
 <head>
  <title>A title</title>
 </head> 
 <body bgcolor = "#ff0000">
  A body
 </body>
</html>