From 0375c0f721d7497113462152bcc155fee4d7bc2c Mon Sep 17 00:00:00 2001
From: Simon Cruanes <simon.cruanes.2007@m4x.org>
Date: Sun, 11 May 2014 18:52:05 +0200
Subject: [PATCH] KMP with sequences

---
 KMP.ml  | 19 +++++++++++++++++++
 KMP.mli |  6 ++++++
 2 files changed, 25 insertions(+)

diff --git a/KMP.ml b/KMP.ml
index dafecace..a49ce282 100644
--- a/KMP.ml
+++ b/KMP.ml
@@ -36,6 +36,7 @@ module type STRING = sig
 end
 
 type 'a gen = unit -> 'a option
+type 'a sequence = ('a -> unit) -> unit
 
 module type S = sig
   type string
@@ -56,12 +57,17 @@ module type S = sig
 
   val find_all : pattern:pattern -> string -> int -> int gen
   (** Generator on all occurrences of the pattern *)
+  
+  val seq : pattern:pattern -> string -> int -> int sequence
+  (** iterate on matching positions *)
 
   (** {6 One-shot functions that compile the pattern on-the-fly} *)
 
   val search' : pattern:string -> string -> int option
 
   val find_all' : pattern:string -> string -> int gen
+
+  val seq' : pattern:string -> string -> int sequence
 end
 
 module Make(Str : STRING) = struct
@@ -141,11 +147,24 @@ module Make(Str : STRING) = struct
           i := j + pattern.len;
           res
 
+  let seq ~pattern s i k =
+    let rec iter i =
+      match find ~pattern s i with
+      | None -> ()
+      | Some j ->
+          k j;
+          iter (j+pattern.len)
+    in
+    iter i
+
   let search' ~pattern s =
     search ~pattern:(compile pattern) s
 
   let find_all' ~pattern s =
     find_all ~pattern:(compile pattern) s 0
+
+  let seq' ~pattern s =
+    seq ~pattern:(compile pattern) s 0
 end
 
 module Default = Make(struct
diff --git a/KMP.mli b/KMP.mli
index a2cc09f6..f431137a 100644
--- a/KMP.mli
+++ b/KMP.mli
@@ -36,6 +36,7 @@ module type STRING = sig
 end
 
 type 'a gen = unit -> 'a option
+type 'a sequence = ('a -> unit) -> unit
 
 module type S = sig
   type string
@@ -56,12 +57,17 @@ module type S = sig
 
   val find_all : pattern:pattern -> string -> int -> int gen
   (** Generator on all occurrences of the pattern *)
+  
+  val seq : pattern:pattern -> string -> int -> int sequence
+  (** iterate on matching positions *)
 
   (** {6 One-shot functions that compile the pattern on-the-fly} *)
 
   val search' : pattern:string -> string -> int option
 
   val find_all' : pattern:string -> string -> int gen
+
+  val seq' : pattern:string -> string -> int sequence
 end
 
 module Make(Str : STRING) : S with type string = Str.t