src/Pure/General/symbol.ML

     if is_ascii_letter s then Letter
     else if is_ascii_digit s then Digit
     else if is_ascii_quasi s then Quasi
     else if is_ascii_blank s then Blank
     else if is_char s then Other
-    else if_none (Symtab.curried_lookup symbol_kinds s) Other;
+    else if_none (Symtab.lookup symbol_kinds s) Other;
 end;
 
 fun is_letter s = kind s = Letter;
 fun is_digit s = kind s = Digit;
 fun is_quasi s = kind s = Quasi;