add Ext_list.find_def

Author: bobzhang

jscomp/ext/ext_list.ml

@@ -583,7 +583,13 @@ let rec find_opt xs p =
     | Some _ as v  ->  v
     | None -> find_opt l p
 
-
+let rec find_def xs p def =
+  match xs with 
+  | [] -> def
+  | x::l -> 
+    match p x with 
+    | Some v -> v 
+    | None -> find_def l p def   
 
 let rec split_map l f = 
   match l with

jscomp/ext/ext_list.mli

@@ -259,7 +259,13 @@ val find_opt :
   ('a -> 'b option) -> 
   'b option 
 
+val find_def : 
+    'a list -> 
+    ('a -> 'b option) ->
+    'b ->
+    'b 
 
+    
 val rev_iter : 
   'a list -> 
   ('a -> unit) ->