--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ProgTutorial/outputfn.ML	Sat May 30 11:12:46 2009 +0200
@@ -0,0 +1,79 @@
+
+structure OutputFN =
+struct
+
+(* rebuilding the output function from ThyOutput in order to *)
+(* enable the options [gray, linenos, index]                   *)
+
+val gray = ref false
+val linenos = ref false
+
+datatype entry = 
+   No_Entry
+ | Code_Entry of string
+ | String_Entry of string
+
+val index = ref No_Entry
+
+fun string_entry s = prefix ("\\index{" ^ s ^ "}")
+fun code_entry   s = prefix ("\\index{" ^ s ^ "@{\\tt\\slshape{}" ^ s ^ "}}")
+
+fun get_word str =
+let 
+  fun only_letters [] = true
+    | only_letters (x::xs) = 
+        if (Symbol.is_ascii_blank x) then false else only_letters xs
+in
+  if (only_letters (Symbol.explode str)) then str
+  else error ("Underspecified index entry only for single words allowed! Error with " ^ str)
+end  
+    
+fun index_entry entry txt =
+ case entry of
+   No_Entry => I
+ | String_Entry "" => string_entry (get_word (implode txt))
+ | String_Entry s  => string_entry s
+ | Code_Entry ""   => code_entry (get_word (implode txt))
+ | Code_Entry s    => code_entry s
+
+
+fun translate f = Symbol.explode #> map f #> implode;
+
+val clean_string = translate
+  (fn "_" => "\\_"
+    | c => c);
+
+fun output txt =
+let
+  val prts = map Pretty.str txt
+in   
+  prts
+  |> (if ! ThyOutput.quotes then map Pretty.quote else I)
+  |> (if ! ThyOutput.display then
+    map (Output.output o Pretty.string_of o Pretty.indent (! ThyOutput.indent))
+    #> space_implode "\\isasep\\isanewline%\n"
+    #> (if ! linenos then (enclose "\\begin{linenos}%\n" "%\n\\end{linenos}") else I) 
+    #> (if ! gray then (enclose "\\begin{graybox}%\n" "%\n\\end{graybox}") else I) 
+    #> enclose "\\begin{isabelle}%\n" "%\n\\end{isabelle}"
+    #> index_entry (!index) txt
+  else
+    map (Output.output o (if ! ThyOutput.break then Pretty.string_of else Pretty.str_of))
+    #> space_implode "\\isasep\\isanewline%\n"
+    #> enclose "\\isa{" "}"
+    #> index_entry (!index) txt)
+end
+
+
+fun boolean "" = true
+  | boolean "true" = true
+  | boolean "false" = false
+  | boolean s = error ("Bad boolean value: " ^ quote s);
+
+val _ = ThyOutput.add_options
+ [("gray", Library.setmp gray o boolean),
+  ("linenos", Library.setmp linenos o boolean),
+  ("index", Library.setmp index o String_Entry o clean_string),
+  ("indexc", Library.setmp index o Code_Entry o clean_string)]
+
+
+end
\ No newline at end of file