diff --git a/src/Control/Lens/Lens.idr b/src/Control/Lens/Lens.idr
index 648dbad..edd738d 100644
--- a/src/Control/Lens/Lens.idr
+++ b/src/Control/Lens/Lens.idr
@@ -154,7 +154,7 @@ infix 4 <||=; infix 4 <&&=; infix 4 <<+>=
 infix 4 <<%=; infix 4 <<%@=; infix 4 <<.=; infix 4 <<?=; infix 4 <<+=; infix 4 <<*=
 infix 4 <<-=; infix 4 <</=; infix 4 <<||=; infix 4 <<&&=; infix 4 <<<+>=
 
-infixr 2 <<~
+infixr 1 <<<~
 
 
 public export
@@ -403,11 +403,8 @@ public export
 
 
 ||| Run a monadic action and set the focus of an optic in state to the result.
-||| This is different from `(<~)` in that it also passes though the output of
-||| the action.
+||| This is different from `(<~)` and `(<<~)` in that it also passes though
+||| the old value of the optic.
 public export
-(<<~) : MonadState s m => Lens s s a b -> m b -> m b
-(<<~) l x = do
-  v <- x
-  modify $ l @{MkIsLens Function} (const v)
-  pure v
+(<<<~) : MonadState s m => Lens s s a b -> m b -> m a
+(<<<~) l m = l <<.= !m
diff --git a/src/Control/Lens/Setter.idr b/src/Control/Lens/Setter.idr
index 068e411..cd82eb5 100644
--- a/src/Control/Lens/Setter.idr
+++ b/src/Control/Lens/Setter.idr
@@ -157,6 +157,8 @@ infix 4 %=; infix 4 %@=; infix 4 .=; infix 4 .@=; infix 4 ?=; infix 4 <.=
 infix 4 <?=; infix 4 +=; infix 4 *=; infix 4 -=; infix 4 //=; infix 4 ||=
 infix 4 &&=; infixr 4 <+>=
 
+infix 1 <~
+infixr 1 <<~
 
 ||| Set the focus of an optic to `Just` a value.
 public export
@@ -303,4 +305,11 @@ public export
 ||| variable.
 public export
 (<~) : MonadState s m => Setter s s a b -> m b -> m ()
-(<~) l m = m >>= (l .=)
+(<~) l m = l .= !m
+
+||| Run a monadic action and set the focus of an optic in state to the result.
+||| This is different from `(<~)` in that it also passes though the output of
+||| the action.
+public export
+(<<~) : MonadState s m => Setter s s a b -> m b -> m b
+(<<~) l m = l <.= !m