The IO

---

(module io mzscheme 
  
  (provide 
   read-all ;; String -> [Listof String]
   ;; read a file as a list of strings 
   
   print-all ;; OutputPort [Listof String] -> Void
   ;; print a list of lines to output port 
   
   directory-exists? ;; String -> Boolean 
   ;; does the string represent a legal path to a directory/folder?
   
   file-exists? ;; String -> Boolean
   ;; does the string represent a legal path to a file? 
   )

   ... definitions ...
)

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full code