    {-# LANGUAGE FlexibleInstances, FlexibleContexts, MultiParamTypeClasses #-}
    {-# LANGUAGE PatternSynonyms #-}

    --------------------------------------------------------------------------------
    -- |
    -- Module      :  XMonad.Layout.StateFull
    -- Description :  The StateFull Layout & FocusTracking Layout Transformer
    -- Copyright   :  (c) 2018  L. S. Leary
    -- License     :  BSD3-style (see LICENSE)
    --
    -- Maintainer  :  L. S. Leary
    -- Stability   :  unstable
    -- Portability :  unportable
    --
    -- Provides StateFull: a stateful form of Full that does not misbehave when
    -- floats are focused, and the FocusTracking layout transformer by means of
    -- which StateFull is implemented. FocusTracking simply holds onto the last
    -- true focus it was given and continues to use it as the focus for the
    -- transformed layout until it sees another. It can be used to improve the
    -- behaviour of a child layout that has not been given the focused window.
    --------------------------------------------------------------------------------

    module XMonad.Layout.StateFull {-# DEPRECATED "Use X.L.TrackFloating." #-} (
      -- * Usage
      -- $Usage
      pattern StateFull,
      StateFull,
      FocusTracking,
      F.focusTracking
    ) where

    import XMonad
    import XMonad.Layout.LayoutModifier
    import qualified XMonad.Layout.FocusTracking as F

    -- $Usage
    --
    -- To use it, first you need to:
    --
    -- > import XMonad.Layout.StateFull
    --
    -- Then to toggle your tiled layout with @StateFull@, you can do:
    --
    -- > main = xmonad def { layoutHook = someTiledLayout ||| StateFull }
    --
    -- Or, some child layout that depends on focus information can be made to fall
    -- back on the last focus it had:
    --
    -- > main = xmonad def
    -- >  { layoutHook = someParentLayoutWith aChild (focusTracking anotherChild) }

    -- | The @FocusTracking@ type for which the @LayoutClass@ instance is provided.
    type FocusTracking = ModifiedLayout F.FocusTracking

    -- | A type synonym to match the @StateFull@ pattern synonym.
    type StateFull = FocusTracking Full

    -- | A pattern synonym for the primary use case of the @FocusTracking@
    --   transformer; using @Full@.
    pattern StateFull :: StateFull a
    pattern $mStateFull :: forall {r} {a}. StateFull a -> ((# #) -> r) -> ((# #) -> r) -> r
    $bStateFull :: forall a. StateFull a
    StateFull = ModifiedLayout (F.FocusTracking Nothing) Full