diff options
Diffstat (limited to 'lib/util.ml')
| -rw-r--r-- | lib/util.ml | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/lib/util.ml b/lib/util.ml index e17e586c20..c733ed3335 100644 --- a/lib/util.ml +++ b/lib/util.ml @@ -141,6 +141,24 @@ let list_fold_left_i f = in it_list_f +(* [list_fold_right_and_left f [a1;...;an] hd = + f (f (... (f (f hd + an + [an-1;...;a1]) + an-1 + [an-2;...;a1]) + ...) + a2 + [a1]) + a1 + []] *) + +let rec list_fold_right_and_left f l hd = + let rec aux tl = function + | [] -> hd + | a::l -> let hd = aux (a::tl) l in f hd a tl + in aux [] l + let list_iter_i f l = list_fold_left_i (fun i _ x -> f i x) 0 () l let list_for_all_i p = |