support older transformers

Author: ulysses4ever

FixWhitespace.hs

@@ -5,7 +5,7 @@
 module Main where
 
 import Control.Monad
-import Control.Monad.Trans.Writer.CPS
+import Control.Monad.Trans.Writer.Strict
 import Control.Exception (IOException, handle)
 
 import Data.Char as Char

fix-whitespace.cabal

@@ -60,7 +60,7 @@ executable fix-whitespace
                 , filepattern  >= 0.1.3    &&  < 0.2
                     -- filepattern 0.1.3 fixes issue fix-whitespace#9
                 , text         >= 1.2.3.0  &&  < 1.3   || == 2.0.*
-                , transformers >= 0.5.6    &&  < 0.6
+                , transformers >= 0.5.2.0  &&  < 0.7
                 , yaml         >= 0.8.4    &&  < 0.12
 
   -- ASR (2018-10-16).