Merge PR #6506: Fast rel lookup

1 files changed, 37 insertions, 0 deletions

diff --git a/clib/range.mli b/clib/range.mli
new file mode 100644
index 0000000000..ae7684ffa5
--- /dev/null
+++ b/clib/range.mli
@@ -0,0 +1,37 @@
+(************************************************************************)
+(*  v      *   The Coq Proof Assistant  /  The Coq Development Team     *)
+(* <O___,, *   INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2016     *)
+(*   \VV/  **************************************************************)
+(*    //   *      This file is distributed under the terms of the       *)
+(*         *       GNU Lesser General Public License Version 2.1        *)
+(************************************************************************)
+
+(** Skewed lists
+
+    This is a purely functional datastructure isomorphic to usual lists, except
+    that it features a O(log n) lookup while preserving the O(1) cons operation.
+
+*)
+
+(** {5 Constructors} *)
+
+type +'a t
+
+val empty : 'a t
+val cons : 'a -> 'a t -> 'a t
+
+(** {5 List operations} *)
+
+val is_empty : 'a t -> bool
+val length : 'a t -> int
+val map : ('a -> 'b) -> 'a t -> 'b t
+val fold_left : ('a -> 'b -> 'a) -> 'a -> 'b t -> 'a
+val fold_right : ('a -> 'b -> 'b) -> 'a t -> 'b -> 'b
+val hd : 'a t -> 'a
+val tl : 'a t -> 'a t
+
+val skipn : int -> 'a t -> 'a t
+
+(** {5 Indexing operations} *)
+
+val get : 'a t -> int -> 'a