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diff --git a/src/System/IO/Terminal/Characters.hs b/src/System/IO/Terminal/Characters.hs
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+++ b/src/System/IO/Terminal/Characters.hs
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+{-|
+Module      : System.IO.Terminal.Characters
+Copyright   : (c) UU, 2019
+License     : MIT
+Maintainer  : Tom Smeding
+Stability   : experimental
+Portability : POSIX, macOS, Windows
+
+Access to a small database of box-drawing characters.
+-}
+module System.IO.Terminal.Characters
+    (boxChar, BoxChar, BoxWeight(..))
+    where
+
+import qualified Data.Map.Strict as Map
+
+
+-- | Description of a box-drawing character: (up, right, down, left)
+type BoxChar = (BoxWeight, BoxWeight, BoxWeight, BoxWeight)
+
+-- | Description of one arm of a box-drawing character.
+data BoxWeight = BoxNone | BoxSingle | BoxHeavy | BoxDouble
+  deriving (Eq, Ord, Show)
+
+-- | Look up a box drawing character in the unicode table. Note that not
+-- all combinations are valid; currently, the function throws an error if
+-- the character doesn't exist.
+boxChar :: BoxChar -> Char
+boxChar tup = mapping Map.! tup
+  where
+    mapping = Map.fromList
+        [((BoxNone, BoxNone, BoxNone, BoxSingle), '╴')
+        ,((BoxNone, BoxNone, BoxNone, BoxHeavy), '╸')
+        ,((BoxSingle, BoxNone, BoxNone, BoxNone), '╵')
+        ,((BoxHeavy, BoxNone, BoxNone, BoxNone), '╹')
+        ,((BoxNone, BoxSingle, BoxNone, BoxNone), '╶')
+        ,((BoxNone, BoxHeavy, BoxNone, BoxNone), '╺')
+        ,((BoxNone, BoxNone, BoxSingle, BoxNone), '╷')
+        ,((BoxNone, BoxNone, BoxHeavy, BoxNone), '╻')
+        ,((BoxNone, BoxSingle, BoxNone, BoxSingle), '─')
+        ,((BoxNone, BoxHeavy, BoxNone, BoxHeavy), '━')
+        ,((BoxNone, BoxHeavy, BoxNone, BoxSingle), '╼')
+        ,((BoxNone, BoxSingle, BoxNone, BoxHeavy), '╾')
+        ,((BoxSingle, BoxNone, BoxSingle, BoxNone), '│')
+        ,((BoxHeavy, BoxNone, BoxHeavy, BoxNone), '┃')
+        ,((BoxSingle, BoxNone, BoxHeavy, BoxNone), '╽')
+        ,((BoxHeavy, BoxNone, BoxSingle, BoxNone), '╿')
+        ,((BoxNone, BoxSingle, BoxSingle, BoxNone), '┌')
+        ,((BoxNone, BoxHeavy, BoxSingle, BoxNone), '┍')
+        ,((BoxNone, BoxSingle, BoxHeavy, BoxNone), '┎')
+        ,((BoxNone, BoxHeavy, BoxHeavy, BoxNone), '┏')
+        ,((BoxNone, BoxNone, BoxSingle, BoxSingle), '┐')
+        ,((BoxNone, BoxNone, BoxSingle, BoxHeavy), '┑')
+        ,((BoxNone, BoxNone, BoxHeavy, BoxSingle), '┒')
+        ,((BoxNone, BoxNone, BoxHeavy, BoxHeavy), '┓')
+        ,((BoxSingle, BoxSingle, BoxNone, BoxNone), '└')
+        ,((BoxSingle, BoxHeavy, BoxNone, BoxNone), '┕')
+        ,((BoxHeavy, BoxSingle, BoxNone, BoxNone), '┖')
+        ,((BoxHeavy, BoxHeavy, BoxNone, BoxNone), '┗')
+        ,((BoxSingle, BoxNone, BoxNone, BoxSingle), '┘')
+        ,((BoxSingle, BoxNone, BoxNone, BoxHeavy), '┙')
+        ,((BoxHeavy, BoxNone, BoxNone, BoxSingle), '┚')
+        ,((BoxHeavy, BoxNone, BoxNone, BoxHeavy), '┛')
+        ,((BoxSingle, BoxSingle, BoxSingle, BoxNone), '├')
+        ,((BoxSingle, BoxHeavy, BoxSingle, BoxNone), '┝')
+        ,((BoxHeavy, BoxSingle, BoxSingle, BoxNone), '┞')
+        ,((BoxSingle, BoxSingle, BoxHeavy, BoxNone), '┟')
+        ,((BoxHeavy, BoxSingle, BoxHeavy, BoxNone), '┠')
+        ,((BoxHeavy, BoxHeavy, BoxSingle, BoxNone), '┡')
+        ,((BoxSingle, BoxHeavy, BoxHeavy, BoxNone), '┢')
+        ,((BoxHeavy, BoxHeavy, BoxHeavy, BoxNone), '┣')
+        ,((BoxSingle, BoxNone, BoxSingle, BoxSingle), '┤')
+        ,((BoxSingle, BoxNone, BoxSingle, BoxHeavy), '┥')
+        ,((BoxHeavy, BoxNone, BoxSingle, BoxSingle), '┦')
+        ,((BoxSingle, BoxNone, BoxHeavy, BoxSingle), '┧')
+        ,((BoxHeavy, BoxNone, BoxHeavy, BoxSingle), '┨')
+        ,((BoxHeavy, BoxNone, BoxSingle, BoxHeavy), '┩')
+        ,((BoxSingle, BoxNone, BoxHeavy, BoxHeavy), '┪')
+        ,((BoxHeavy, BoxNone, BoxHeavy, BoxHeavy), '┫')
+        ,((BoxNone, BoxSingle, BoxSingle, BoxSingle), '┬')
+        ,((BoxNone, BoxSingle, BoxSingle, BoxHeavy), '┭')
+        ,((BoxNone, BoxHeavy, BoxSingle, BoxSingle), '┮')
+        ,((BoxNone, BoxHeavy, BoxSingle, BoxHeavy), '┯')
+        ,((BoxNone, BoxSingle, BoxHeavy, BoxSingle), '┰')
+        ,((BoxNone, BoxSingle, BoxHeavy, BoxHeavy), '┱')
+        ,((BoxNone, BoxHeavy, BoxHeavy, BoxSingle), '┲')
+        ,((BoxNone, BoxHeavy, BoxHeavy, BoxHeavy), '┳')
+        ,((BoxSingle, BoxSingle, BoxNone, BoxSingle), '┴')
+        ,((BoxSingle, BoxSingle, BoxNone, BoxHeavy), '┵')
+        ,((BoxSingle, BoxHeavy, BoxNone, BoxSingle), '┶')
+        ,((BoxSingle, BoxHeavy, BoxNone, BoxHeavy), '┷')
+        ,((BoxHeavy, BoxSingle, BoxNone, BoxSingle), '┸')
+        ,((BoxHeavy, BoxSingle, BoxNone, BoxHeavy), '┹')
+        ,((BoxHeavy, BoxHeavy, BoxNone, BoxSingle), '┺')
+        ,((BoxHeavy, BoxHeavy, BoxNone, BoxHeavy), '┻')
+        ,((BoxSingle, BoxSingle, BoxSingle, BoxSingle), '┼')
+        ,((BoxSingle, BoxSingle, BoxSingle, BoxHeavy), '┽')
+        ,((BoxSingle, BoxHeavy, BoxSingle, BoxSingle), '┾')
+        ,((BoxSingle, BoxHeavy, BoxSingle, BoxHeavy), '┿')
+        ,((BoxHeavy, BoxSingle, BoxSingle, BoxSingle), '╀')
+        ,((BoxSingle, BoxSingle, BoxHeavy, BoxSingle), '╁')
+        ,((BoxHeavy, BoxSingle, BoxHeavy, BoxSingle), '╂')
+        ,((BoxHeavy, BoxSingle, BoxSingle, BoxHeavy), '╃')
+        ,((BoxHeavy, BoxHeavy, BoxSingle, BoxSingle), '╄')
+        ,((BoxSingle, BoxSingle, BoxHeavy, BoxHeavy), '╅')
+        ,((BoxSingle, BoxHeavy, BoxHeavy, BoxSingle), '╆')
+        ,((BoxHeavy, BoxHeavy, BoxSingle, BoxHeavy), '╇')
+        ,((BoxSingle, BoxHeavy, BoxHeavy, BoxHeavy), '╈')
+        ,((BoxHeavy, BoxSingle, BoxHeavy, BoxHeavy), '╉')
+        ,((BoxHeavy, BoxHeavy, BoxHeavy, BoxSingle), '╊')
+        ,((BoxHeavy, BoxHeavy, BoxHeavy, BoxHeavy), '╋')
+        ,((BoxNone, BoxDouble, BoxNone, BoxDouble), '═')
+        ,((BoxDouble, BoxNone, BoxDouble, BoxNone), '║')
+        ,((BoxNone, BoxDouble, BoxSingle, BoxNone), '╒')
+        ,((BoxNone, BoxSingle, BoxDouble, BoxNone), '╓')
+        ,((BoxNone, BoxDouble, BoxDouble, BoxNone), '╔')
+        ,((BoxNone, BoxNone, BoxSingle, BoxDouble), '╕')
+        ,((BoxNone, BoxNone, BoxDouble, BoxSingle), '╖')
+        ,((BoxNone, BoxNone, BoxDouble, BoxDouble), '╗')
+        ,((BoxSingle, BoxDouble, BoxNone, BoxNone), '╘')
+        ,((BoxDouble, BoxSingle, BoxNone, BoxNone), '╙')
+        ,((BoxDouble, BoxDouble, BoxNone, BoxNone), '╚')
+        ,((BoxSingle, BoxNone, BoxNone, BoxDouble), '╛')
+        ,((BoxDouble, BoxNone, BoxNone, BoxSingle), '╜')
+        ,((BoxDouble, BoxNone, BoxNone, BoxDouble), '╝')
+        ,((BoxSingle, BoxDouble, BoxSingle, BoxNone), '╞')
+        ,((BoxDouble, BoxSingle, BoxDouble, BoxNone), '╟')
+        ,((BoxDouble, BoxDouble, BoxDouble, BoxNone), '╠')
+        ,((BoxSingle, BoxNone, BoxSingle, BoxDouble), '╡')
+        ,((BoxDouble, BoxNone, BoxDouble, BoxSingle), '╢')
+        ,((BoxDouble, BoxNone, BoxDouble, BoxDouble), '╣')
+        ,((BoxNone, BoxDouble, BoxSingle, BoxDouble), '╤')
+        ,((BoxNone, BoxSingle, BoxDouble, BoxSingle), '╥')
+        ,((BoxNone, BoxDouble, BoxDouble, BoxDouble), '╦')
+        ,((BoxSingle, BoxDouble, BoxNone, BoxDouble), '╧')
+        ,((BoxDouble, BoxSingle, BoxNone, BoxSingle), '╨')
+        ,((BoxDouble, BoxDouble, BoxNone, BoxDouble), '╩')
+        ,((BoxSingle, BoxDouble, BoxSingle, BoxDouble), '╪')
+        ,((BoxDouble, BoxSingle, BoxDouble, BoxSingle), '╫')
+        ,((BoxDouble, BoxDouble, BoxDouble, BoxDouble), '╬')]