From 63d105d54b6343235935d81937b207881c5145fe Mon Sep 17 00:00:00 2001
From: Josh Berdine <jjb@fb.com>
Date: Tue, 29 Nov 2016 16:31:37 -0800
Subject: [PATCH] ppx_compare IList

Reviewed By: cristianoc

Differential Revision: D4232365

fbshipit-source-id: 853f6df
---
 infer/src/base/IList.ml  | 19 +++++--------------
 infer/src/base/IList.mli |  5 ++---
 2 files changed, 7 insertions(+), 17 deletions(-)

diff --git a/infer/src/base/IList.ml b/infer/src/base/IList.ml
index 32c110f69..8f28efb72 100644
--- a/infer/src/base/IList.ml
+++ b/infer/src/base/IList.ml
@@ -7,6 +7,11 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  *)
 
+type 'a t = 'a list [@@deriving compare]
+
+let equal cmp l1 l2 =
+  compare cmp l1 l2 = 0
+
 let exists = List.exists
 let filter = List.filter
 let find = List.find
@@ -83,20 +88,6 @@ let rec drop_first n = function
 let drop_last n list =
   rev (drop_first n (rev list))
 
-(** Generic comparison of lists given a compare function for the elements of the list *)
-let rec compare cmp l1 l2 =
-  match l1, l2 with
-  | [],[] -> 0
-  | [], _ -> - 1
-  | _, [] -> 1
-  | x1:: l1', x2:: l2' ->
-      let n = cmp x1 x2 in
-      if n <> 0 then n else compare cmp l1' l2'
-
-(** Generic equality of lists given a compare function for the elements of the list *)
-let equal cmp l1 l2 =
-  compare cmp l1 l2 = 0
-
 (** Returns (reverse input_list) *)
 let rec rev_with_acc acc = function
   | [] -> acc
diff --git a/infer/src/base/IList.mli b/infer/src/base/IList.mli
index 71574492b..cb37354db 100644
--- a/infer/src/base/IList.mli
+++ b/infer/src/base/IList.mli
@@ -7,11 +7,10 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  *)
 
-(** Generic comparison of lists given a compare function for the elements of the list *)
-val compare : ('a -> 'b -> int) -> 'a list -> 'b list -> int
+type 'a t = 'a list [@@deriving compare]
 
 (** Generic equality of lists given a compare function for the elements of the list *)
-val equal : ('a -> 'b -> int) -> 'a list -> 'b list -> bool
+val equal : ('a -> 'a -> int) -> 'a list -> 'a list -> bool
 
 (** tail-recursive variant of List.append *)
 val append : 'a list -> 'a list -> 'a list