src/Pure/General/seq.ML

   (case pull xq of
     NONE => []
   | SOME (x, xq') => x :: list_of xq');
 
 (*conversion from list to sequence*)
-fun of_list xs = Library.foldr cons (xs, empty);
+fun of_list xs = foldr cons empty xs;
 
 
 (*map the function f over the sequence, making a new sequence*)
 fun map f xq =
   make (fn () =>

   | some => make (fn () => some));
 
 fun op APPEND (f, g) x =
   append (f x, make (fn () => pull (g x)));
 
-fun EVERY fs = Library.foldr THEN (fs, succeed);
-fun FIRST fs = Library.foldr ORELSE (fs, fail);
+fun EVERY fs = foldr THEN succeed fs;
+fun FIRST fs = foldr ORELSE fail fs;
 
 fun TRY f = ORELSE (f, succeed);
 
 fun REPEAT f =
   let