Add string->symbol to DeinProgramm / DMdA advanced.

Also, exclude symbol-related stuff from everything below.

svn: r17082

collects/deinprogramm/DMdA-assignments.ss

@@ -19,5 +19,5 @@
  procedures
  (all-from-except assignments: deinprogramm/DMdA procedures
 		  quote
-		  symbol?))
+		  symbol? string->symbol symbol->string))
 

collects/deinprogramm/DMdA-beginner.ss

@@ -18,5 +18,5 @@
 		  quote
 		  make-pair pair? first rest
 		  length map for-each reverse append list list-ref fold
-		  symbol?
+		  symbol? string->symbol symbol->string
 		  apply))

collects/deinprogramm/DMdA-vanilla.ss

@@ -17,5 +17,5 @@
 		  quote eq? equal?
 		  set!
 		  define-record-procedures-2
-		  symbol?
+		  symbol? string->symbol symbol->string
 		  apply))

collects/deinprogramm/DMdA.ss

@@ -316,7 +316,9 @@
   (symbol? (%a -> boolean)
 	   "feststellen, ob ein Wert ein Symbol ist")
   (symbol->string (symbol -> string)
-		  "Symbol in Zeichenkette umwandeln"))
+		  "Symbol in Zeichenkette umwandeln")
+  (string->symbol (string -> symbol)
+		  "Zeichenkette in Symbol umwandeln"))
  
  ("Verschiedenes"
   (equal? (%a %b -> boolean)