add splitAt

1 files changed, 17 insertions, 0 deletions

diff --git a/src/Blessings.hs b/src/Blessings.hs
index 8b55e24..59fc4c8 100644
--- a/src/Blessings.hs
+++ b/src/Blessings.hs
@@ -13,6 +13,7 @@ import Control.Applicative
 import Data.Ix (inRange)
 import Data.List (genericDrop)
 import Data.String
+import Data.Tuple.Extra (both, first, second)
 import Data.Word (Word8)
 import qualified Prelude
 import Prelude hiding (drop, length, take)
@@ -393,6 +394,22 @@ instance (Eq a, Blessable a) => Blessable (Blessings a) where
       Empty ->
           Empty
 
+  splitAt n = \case
+      Append t1 t2 ->
+        both normalize $
+          let
+            nt1 = Bless.length t1
+          in
+            if n <= nt1
+              then second (<>t2) $ Bless.splitAt n t1
+              else first (t1<>) $ Bless.splitAt (n - nt1) t2
+      Plain s ->
+        both (normalize . Plain) $ Bless.splitAt n s
+      SGR pm t ->
+        both (normalize . SGR pm) $ Bless.splitAt n t
+      Empty ->
+        (Empty, Empty)
+
   intercalate i = \case
       [] -> mempty
       [t] -> t