Merge pull request #104744 from adisbladis/unique-foldl

lib.lists.unique: Switch from recursive function to using a fold
2020-11-24 14:55:42 +01:00 · 2020-11-24 14:55:42 +01:00 · 04150a003e
parent 91f1d7e405 85605c8a29
commit 04150a003e
1 changed files with 1 additions and 7 deletions
--- a/lib/lists.nix
+++ b/lib/lists.nix
@ -640,13 +640,7 @@ rec {
       unique [ 3 2 3 4 ]
       => [ 3 2 4 ]
   */
-  unique = list:
-    if list == [] then
-      []
-    else
-      let
-        x = head list;
-      in [x] ++ unique (remove x list);
+ unique = foldl' (acc: e: if elem e acc then acc else acc ++ [ e ]) [];

  /* Intersects list 'e' and another list. O(nm) complexity.