a

9 files changed, 203 insertions, 138 deletions

diff --git a/README.md b/README.md
index 853f1e2..37e4be5 100644
--- a/README.md
+++ b/README.md
@@ -51,14 +51,13 @@ their [documentation](https://jaspervdj.be/blaze/).
 
 ## Unleash the monads
 
-[Text.BlazeT](https://hackage.haskell.org/package/blazeT/docs/Text-BlazeT.html) exports
-`runWith` and `execWith`, which work on any
-`Text.Blaze.Renderer.*`. The rendered markup will be returned within
-the base monad, whose actions can
-be
-[`lift`ed](https://hackage.haskell.org/package/transformers-0.5.2.0/docs/Control-Monad-Trans-Class.html) into
-the Markup, as shown in the following example
-(from [here](src/Readme.hs)):
+[Text.BlazeT](https://hackage.haskell.org/package/blazeT/docs/Text-BlazeT.html)
+exports `runWith` and `execWith`, which work on any
+`Text.BlazeT.Renderer.*`. The rendered markup will be returned within
+the base monad, whose actions can be
+[`lift`ed](https://hackage.haskell.org/package/transformers-0.5.2.0/docs/Control-Monad-Trans-Class.html)
+into the Markup, as shown in the following example (from
+[here](src/Readme.hs)):
 
 ```Haskell
 {-# LANGUAGE OverloadedStrings #-}
@@ -123,8 +122,16 @@ of `Blaze.Markup` and is basically a `WriterT` writing `Blaze.Markup`:
 newtype MarkupT m a = MarkupT { fromMarkupT :: WriterT B.Markup m a }
 ```
 
+The old `Text.Blaze.Markup` type is replaced by a rank-2 version of
+the transformer:
+
+```Haskell
+type Markup = forall m . Monad m => MarkupT m ()
+```
+
 Wrappers used to lift all `Blaze` entities into `BlazeT` are trivially
-expressible using basic `WriterT` class methods. Wrapping `Blaze.Markup` is simply `WriterT.tell`:
+expressible using basic `WriterT` class methods. Wrapping
+`Blaze.Markup` is simply `WriterT.tell`:
 
 ```Haskell
 wrapMarkupT :: Monad m => B.Markup -> MarkupT m ()
@@ -137,4 +144,3 @@ wrapMarkupT2 :: Monad m => (B.Markup -> B.Markup) -> MarkupT m a -> MarkupT m a
 wrapMarkupT2 = censor
 ```
 
-
diff --git a/Setup.hs b/Setup.hs
index c67c506..7b0e237 100644
--- a/Setup.hs
+++ b/Setup.hs
@@ -3,9 +3,10 @@ import Distribution.Simple.Setup
 import Distribution.Simple.Haddock
 main = do
   defaultMainWithHooks simpleUserHooks{
-    haddockHook = \p l h f -> haddockHook simpleUserHooks p l h f{
+    haddockHook = \p l h flags -> haddockHook simpleUserHooks p l h flags{
         haddockHoogle       = Flag True,
         haddockHtml         = Flag True,
+        haddockProgramArgs  = [("-q",["aliased"])], -- does not seam to do anything
         haddockExecutables  = Flag True,
         haddockHscolour     = Flag True
         }
diff --git a/src/Text/BlazeT.hs b/src/Text/BlazeT.hs
index b3e7c8d..ffdd89b 100644
--- a/src/Text/BlazeT.hs
+++ b/src/Text/BlazeT.hs
@@ -1,19 +1,24 @@
 {-# LANGUAGE UndecidableInstances #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE RankNTypes #-}
+
 module Text.BlazeT
   (
-      -- * Important types.
+   -- * DO NOT READ THIS. READ "Text.BlazeT.Internal" INSTEAD 
+    -- $descr
+    
+   -- * DO NOT READ THIS
+-- -- * Important types.
       Markup
     , Tag
     , Attribute
     , AttributeValue
 
-      -- * Creating attributes.
+-- -- * Creating attributes.
     , dataAttribute
     , customAttribute
 
-      -- * Converting values to Markup.
+-- -- * Converting values to Markup.
     , ToMarkup (..)
     , text
     , preEscapedText
@@ -24,19 +29,19 @@ module Text.BlazeT
     , unsafeByteString
     , unsafeLazyByteString
 
-      -- * Comments
+-- -- * Comments
     , textComment
     , lazyTextComment
     , stringComment
     , unsafeByteStringComment
     , unsafeLazyByteStringComment
 
-      -- * Creating tags.
+-- -- * Creating tags.
     , textTag
     , stringTag
 
-      -- * Converting values to attribute values.
-    , B.ToValue (..)
+-- -- * Converting values to attribute values.
+    , Text.Blaze.ToValue (..)
     , textValue
     , preEscapedTextValue
     , lazyTextValue
@@ -46,28 +51,28 @@ module Text.BlazeT
     , unsafeByteStringValue
     , unsafeLazyByteStringValue
 
-      -- * Setting attributes
+-- -- * Setting attributes
     , (!)
     , (!?)
 
-      -- * Modifiying Markup trees
+-- -- * Modifiying Markup trees
     , contents
 
-    -- * BlazeT new stuff
+    ,MarkupT(..)
+    ,MarkupI
+    ,mapMarkupT
     ,MarkupM
     ,Markup2
-    ,mapMarkupT
-    ,MarkupT
-    ,runMarkup
     ,runMarkupT
-    ,execMarkup
-    ,execMarkupT
+    ,runMarkup
     ,runWith
+    ,execMarkupT
+    ,execMarkup
     ,execWith
     ) where
 
-import qualified Text.Blaze as B
-import           Text.BlazeT.Internal
+import qualified Text.Blaze
+import           Text.BlazeT.Internal as Text.BlazeT.Internal 
 
 class ToMarkup a where
   toMarkup :: a -> Markup
@@ -76,8 +81,20 @@ class ToMarkup a where
 -- test :: (ToMarkup a, Monad m) => a -> MarkupT m ()
 -- test = toMarkup
 
-instance B.ToMarkup a => ToMarkup a where
-  toMarkup = wrapMarkup . B.toMarkup
+instance Text.Blaze.ToMarkup a => ToMarkup a where
+  toMarkup = wrapMarkup . Text.Blaze.toMarkup
   {-# INLINE toMarkup #-}
-  preEscapedToMarkup = wrapMarkup . B.preEscapedToMarkup
+  preEscapedToMarkup = wrapMarkup . Text.Blaze.preEscapedToMarkup
   {-# INLINE preEscapedToMarkup #-}
+
+
+-- $descr
+-- 
+-- Due due a Haddock bug, this documentation is misleading. Please
+-- read "Text.BlazeT.Internal" instead.
+--
+-- (The bug shows both @Text.Blaze.Markup@ and @Text.BlazeT.Markup@ as
+-- "Markup".)
+--
+-- Use this documentation only to see which entities are exported by
+-- this module.
diff --git a/src/Text/BlazeT/Html.hs b/src/Text/BlazeT/Html.hs
index 4a21c03..d71e90a 100644
--- a/src/Text/BlazeT/Html.hs
+++ b/src/Text/BlazeT/Html.hs
@@ -1,18 +1,21 @@
 {-# LANGUAGE RankNTypes #-}
 module Text.BlazeT.Html
-    ( module Text.BlazeT
+    (
+    module Text.BlazeT
+    -- * Entities exported only by the @blazeT@ version of this module
+    ,HtmlM
+    ,HtmlT
+    -- * Entities exported also by "Text.Blaze.Html"
+    -- $descr1
     , Html
     , toHtml
     , preEscapedToHtml
-    -- * BlazeT new stuff
-    ,HtmlM
-    ,HtmlT
     ) where
 
 import Text.BlazeT
 
 type HtmlT = MarkupT
-type HtmlM = MarkupM
+type HtmlM a = MarkupM a
 type Html = Markup
 
 toHtml ::(ToMarkup a) => a -> Html
@@ -20,3 +23,7 @@ toHtml = toMarkup
 
 preEscapedToHtml ::(ToMarkup a) => a -> Html
 preEscapedToHtml = preEscapedToMarkup
+
+-- $descr1 The following is an adaptation of all "Text.Blaze.Html"
+-- exports to @blazeT@ types. For their documentation consult the
+-- "Text.Blaze.Html" documentation.
diff --git a/src/Text/BlazeT/Internal.hs b/src/Text/BlazeT/Internal.hs
index f0c3edb..aa56347 100644
--- a/src/Text/BlazeT/Internal.hs
+++ b/src/Text/BlazeT/Internal.hs
@@ -8,23 +8,49 @@
 #endif
 module Text.BlazeT.Internal
     (
-      -- * Important types.
-      B.ChoiceString (..)
-    , B.StaticString (..)
-    , MarkupM
-    , Markup
-    , B.Tag
-    , B.Attribute
-    , B.AttributeValue
-
-      -- * Creating custom tags and attributes.
+    -- * Entities exported only by the @blazeT@ version of this module
+    MarkupT(..)
+    ,MarkupI
+    ,mapMarkupT
+    -- ** Specializations for @blaze-markup@ backwards compatibility
+    ,MarkupM
+    ,Markup
+    ,Markup2
+    -- ** Running
+    ,runMarkupT
+    ,runMarkup
+    ,runWith
+    -- ** Executing
+    ,execMarkupT
+    ,execMarkup
+    ,execWith
+    -- ** Wrappers
+    ,wrapMarkupT
+    ,wrapMarkupT2
+    ,wrapMarkup
+    ,wrapMarkup2
+    ,
+    
+    -- * Entities exported also by "Text.Blaze.Internal"
+    -- $descr1
+    
+      -- ** Important types.
+      Text.Blaze.ChoiceString (..)
+    , Text.Blaze.StaticString (..)
+    -- , MarkupM
+    -- , Markup
+    , Text.Blaze.Tag
+    , Text.Blaze.Attribute
+    , Text.Blaze.AttributeValue
+
+      -- ** Creating custom tags and attributes.
     , customParent
     , customLeaf
-    , B.attribute
-    , B.dataAttribute
-    , B.customAttribute
+    , Text.Blaze.attribute
+    , Text.Blaze.dataAttribute
+    , Text.Blaze.customAttribute
 
-      -- * Converting values to Markup.
+      -- ** Converting values to Markup.
     , text
     , preEscapedText
     , lazyText
@@ -36,55 +62,41 @@ module Text.BlazeT.Internal
     , unsafeByteString
     , unsafeLazyByteString
 
-      -- * Comments
-    , B.textComment
-    , B.lazyTextComment
-    , B.stringComment
-    , B.unsafeByteStringComment
-    , B.unsafeLazyByteStringComment
-
-      -- * Converting values to tags.
-    , B.textTag
-    , B.stringTag
-
-      -- * Converting values to attribute values.
-    , B.textValue
-    , B.preEscapedTextValue
-    , B.lazyTextValue
-    , B.preEscapedLazyTextValue
-    , B.textBuilderValue
-    , B.preEscapedTextBuilderValue
-    , B.stringValue
-    , B.preEscapedStringValue
-    , B.unsafeByteStringValue
-    , B.unsafeLazyByteStringValue
-
-      -- * Setting attributes
-    , B.Attributable
-    , (B.!)
-    , (B.!?)
-
-      -- * Modifying Markup elements
+      -- ** Comments
+    , Text.Blaze.textComment
+    , Text.Blaze.lazyTextComment
+    , Text.Blaze.stringComment
+    , Text.Blaze.unsafeByteStringComment
+    , Text.Blaze.unsafeLazyByteStringComment
+
+      -- ** Converting values to tags.
+    , Text.Blaze.textTag
+    , Text.Blaze.stringTag
+
+      -- ** Converting values to attribute values.
+    , Text.Blaze.textValue
+    , Text.Blaze.preEscapedTextValue
+    , Text.Blaze.lazyTextValue
+    , Text.Blaze.preEscapedLazyTextValue
+    , Text.Blaze.textBuilderValue
+    , Text.Blaze.preEscapedTextBuilderValue
+    , Text.Blaze.stringValue
+    , Text.Blaze.preEscapedStringValue
+    , Text.Blaze.unsafeByteStringValue
+    , Text.Blaze.unsafeLazyByteStringValue
+
+      -- ** Setting attributes
+    , Text.Blaze.Attributable
+    , (Text.Blaze.!)
+    , (Text.Blaze.!?)
+
+      -- ** Modifying Markup elements
     , contents
     , external
 
-      -- * Querying Markup elements
+      -- ** Querying Markup elements
     , null
 
-    -- * BlazeT new stuff
-    ,Markup2
-    ,mapMarkupT
-    ,MarkupT
-    ,runMarkup
-    ,runMarkupT
-    ,execMarkup
-    ,execMarkupT
-    ,wrapMarkup
-    ,wrapMarkupT
-    ,wrapMarkup2
-    ,wrapMarkupT2
-    ,runWith
-    ,execWith
   ) where
 
 import           Control.Arrow
@@ -97,58 +109,63 @@ import           Data.String
 import qualified Data.Text as T
 import qualified Data.Text.Lazy as LT
 import qualified Data.Text.Lazy.Builder as LTB
-import qualified Text.Blaze as B
-import qualified Text.Blaze.Internal as B
-
-newtype MarkupT m a= MarkupT { fromMarkupT :: WriterT B.Markup m a }
+import qualified Text.Blaze
+import qualified Text.Blaze.Internal as Text.Blaze
+
+{- | Everything is build around the simple @newtype@ definition of the
+'MarkupT' transformer, which makes use the 'Monoid' instance of Blaze
+'Text.Blaze.Markup' and is basically a 'WriterT' writing Blaze
+'Text.Blaze.Markup':
+-}
+newtype MarkupT m a= MarkupT { fromMarkupT :: WriterT Text.Blaze.Markup m a }
                      deriving (Functor
 #if MIN_VERSION_base(4,8,0)
                               ,Applicative
 #endif
                               ,Monad
-                              ,MonadWriter B.Markup
+                              ,MonadWriter Text.Blaze.Markup
                               ,MonadTrans
                               )
 
+type MarkupI a = MarkupT Identity a
+
 -- | Map both the return value and markup of a computation using the
 -- given function
-mapMarkupT :: (m (a,B.Markup) -> n (b,B.Markup)) -> MarkupT m a -> MarkupT n b
+mapMarkupT :: (m (a,Text.Blaze.Markup) -> n (b,Text.Blaze.Markup)) -> MarkupT m a -> MarkupT n b
 mapMarkupT f = MarkupT . mapWriterT f . fromMarkupT
 {-# INLINE mapMarkupT #-}
 
-type MarkupM = MarkupT Identity
-type Markup = forall m . Monad m => MarkupT m ()
+type MarkupM a = forall m . Monad m => MarkupT m a
+type Markup = MarkupM ()
 type Markup2 = forall m . Monad m => MarkupT m () -> MarkupT m ()
 
-runMarkupT :: MarkupT m a -> m (a,B.Markup)
+runMarkupT :: MarkupT m a -> m (a,Text.Blaze.Markup)
 runMarkupT = runWriterT . fromMarkupT
 {-# INLINE runMarkupT #-}
 
 -- | run the MarkupT and return a pair consisting of the result of the
 -- computation and the blaze markup rendered with a blaze renderer
--- like 'Text.Blaze.Renderer.Text.renderHtml'
-runWith :: Monad m => (MarkupM () -> c) -> MarkupT m a -> m (a, c)
-runWith renderer = liftM (second $ renderer . wrapMarkup) . runMarkupT  
+-- like 'Text.BlazeT.Renderer.Text.renderHtml'
+runWith :: Monad m => (Markup -> c) -> MarkupT m a -> m (a, c)
+runWith renderer =  liftM (second $ \x -> renderer $ wrapMarkup x) . runMarkupT  
 {-# INLINE runWith #-}
   
-execMarkupT :: Monad m => MarkupT m a -> m B.Markup
+execMarkupT :: Monad m => MarkupT m a -> m Text.Blaze.Markup
 execMarkupT = liftM snd . runMarkupT
 {-# INLINE execMarkupT #-}
 
-execWith :: Monad m => (MarkupM () -> c) -> MarkupT m a -> m c
+execWith :: Monad m => (Markup -> c) -> MarkupT m a -> m c
 execWith renderer = liftM snd . runWith renderer
 {-# INLINE execWith #-}
 
-runMarkup :: MarkupM a -> (a,B.Markup)
+runMarkup :: MarkupI a -> (a, Text.Blaze.Markup)
 runMarkup = runIdentity . runMarkupT
 {-# INLINE runMarkup #-}
 
-execMarkup :: MarkupM a -> B.Markup
+execMarkup :: MarkupI a -> Text.Blaze.Markup
 execMarkup = snd . runMarkup
 {-# INLINE execMarkup #-}
 
--- instance MonadTrans MarkupT where
-
 
 instance (Monad m,Monoid a) => Monoid (MarkupT m a) where
   mempty = return mempty
@@ -157,37 +174,42 @@ instance (Monad m,Monoid a) => Monoid (MarkupT m a) where
   {-# INLINE mappend #-}
 
 
-instance Monad m => B.Attributable (MarkupT m a) where
-  h ! a = wrapMarkupT2 (B.! a) h
+instance Monad m => Text.Blaze.Attributable (MarkupT m a) where
+  h ! a = wrapMarkupT2 (Text.Blaze.! a) h
   {-# INLINE (!) #-}
 
-instance Monad m => B.Attributable (a -> MarkupT m b) where
-  h ! a = \x -> wrapMarkupT2 (B.! a) $ h x
+instance Monad m => Text.Blaze.Attributable (a -> MarkupT m b) where
+  h ! a = \x -> wrapMarkupT2 (Text.Blaze.! a) $ h x
   {-# INLINE (!) #-}
 
 instance Monad m => IsString (MarkupT m ()) where
   fromString = wrapMarkup . fromString
   {-# INLINE fromString #-}
 
-wrapMarkupT :: Monad m => B.Markup -> MarkupT m ()
+-- | Wrapper for 'Text.Blaze.Markup' is simply
+-- 'tell'
+wrapMarkupT :: Monad m => Text.Blaze.Markup -> MarkupT m ()
 wrapMarkupT = tell
 {-# INLINE wrapMarkupT #-}
 
-wrapMarkup :: B.Markup -> Markup
+wrapMarkup :: Text.Blaze.Markup -> Markup
 wrapMarkup = wrapMarkupT
 {-# INLINE wrapMarkup #-}
 
-wrapMarkupT2 ::  Monad m => (B.Markup -> B.Markup)
+
+-- | Wrapper for functions that modify 'Text.Blaze.Markup' is simply
+-- 'censor'
+wrapMarkupT2 ::  Monad m => (Text.Blaze.Markup -> Text.Blaze.Markup)
                  -> MarkupT m a -> MarkupT m a
 wrapMarkupT2 = censor
 {-# INLINE wrapMarkupT2 #-}
 
-wrapMarkup2 :: (B.Markup -> B.Markup) -> Markup2
+wrapMarkup2 :: (Text.Blaze.Markup -> Text.Blaze.Markup) -> Markup2
 wrapMarkup2 = wrapMarkupT2
 {-# INLINE wrapMarkup2 #-}
 
 unsafeByteString :: BS.ByteString -> Markup
-unsafeByteString = wrapMarkup . B.unsafeByteString
+unsafeByteString = wrapMarkup . Text.Blaze.unsafeByteString
 {-# INLINE unsafeByteString #-}
 
 -- | Insert a lazy 'BL.ByteString'. See 'unsafeByteString' for reasons why this
@@ -195,39 +217,39 @@ unsafeByteString = wrapMarkup . B.unsafeByteString
 --
 unsafeLazyByteString :: BL.ByteString  -- ^ Value to insert
                      -> Markup         -- ^ Resulting HTML fragment
-unsafeLazyByteString = wrapMarkup . B.unsafeLazyByteString
+unsafeLazyByteString = wrapMarkup . Text.Blaze.unsafeLazyByteString
 {-# INLINE unsafeLazyByteString #-}
 
 external :: Monad m => MarkupT m a -> MarkupT m a
-external = wrapMarkupT2  B.external
+external = wrapMarkupT2  Text.Blaze.external
 {-# INLINE external #-}
 
 contents :: Monad m => MarkupT m a -> MarkupT m a
-contents = wrapMarkupT2  B.contents
+contents = wrapMarkupT2  Text.Blaze.contents
 {-# INLINE contents #-}
 
-customParent ::B.Tag -> Markup2
-customParent = wrapMarkup2 . B.customParent
+customParent ::Text.Blaze.Tag -> Markup2
+customParent = wrapMarkup2 . Text.Blaze.customParent
 {-# INLINE customParent #-}
 
-customLeaf :: B.Tag -> Bool -> Markup
-customLeaf = fmap wrapMarkup . B.customLeaf
+customLeaf :: Text.Blaze.Tag -> Bool -> Markup
+customLeaf = fmap wrapMarkup . Text.Blaze.customLeaf
 {-# INLINE customLeaf #-}
 
 preEscapedText :: T.Text -> Markup
-preEscapedText = wrapMarkup . B.preEscapedText
+preEscapedText = wrapMarkup . Text.Blaze.preEscapedText
 {-# INLINE preEscapedText #-}
 
 preEscapedLazyText :: LT.Text -> Markup
-preEscapedLazyText = wrapMarkup . B.preEscapedLazyText
+preEscapedLazyText = wrapMarkup . Text.Blaze.preEscapedLazyText
 {-# INLINE preEscapedLazyText #-}
 
 preEscapedTextBuilder :: LTB.Builder -> Markup
 textBuilder :: LTB.Builder -> Markup
 
 #ifdef PRE_BUILDER
-preEscapedTextBuilder = wrapMarkup . B.preEscapedTextBuilder
-textBuilder = wrapMarkup . B.textBuilder
+preEscapedTextBuilder = wrapMarkup . Text.Blaze.preEscapedTextBuilder
+textBuilder = wrapMarkup . Text.Blaze.textBuilder
 {-# INLINE preEscapedTextBuilder #-}
 {-# INLINE textBuilder #-}
 #else
@@ -236,17 +258,27 @@ textBuilder = error "This function needs blaze-markup 0.7.1.0"
 #endif
 
 preEscapedString :: String -> Markup
-preEscapedString = wrapMarkup . B.preEscapedString
+preEscapedString = wrapMarkup . Text.Blaze.preEscapedString
 {-# INLINE preEscapedString #-}
 
 string :: String -> Markup
-string = wrapMarkup . B.string
+string = wrapMarkup . Text.Blaze.string
 {-# INLINE string #-}
 
 text :: T.Text -> Markup
-text = wrapMarkup . B.text
+text = wrapMarkup . Text.Blaze.text
 {-# INLINE text #-}
 
 lazyText :: LT.Text -> Markup
-lazyText = wrapMarkup . B.lazyText
+lazyText = wrapMarkup . Text.Blaze.lazyText
 {-# INLINE lazyText #-}
+
+-- $descr1
+-- The following is an adaptation of all "Text.Blaze.Internal" exports to
+-- @blazeT@ types.
+-- 
+-- Entities that are reexported from "Text.Blaze.Internal" have the original
+-- documentation attached to them.
+--
+-- Entities that had to be adapted are tagged with \"(Adapted)\". For
+-- their documentation consult the "Text.Blaze.Internal" documentation.
diff --git a/src/Text/BlazeT/Renderer/Pretty.hs b/src/Text/BlazeT/Renderer/Pretty.hs
index fa8cdad..5e033ac 100644
--- a/src/Text/BlazeT/Renderer/Pretty.hs
+++ b/src/Text/BlazeT/Renderer/Pretty.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE RankNTypes #-}
 module Text.BlazeT.Renderer.Pretty
     ( renderMarkup
     , renderHtml
diff --git a/src/Text/BlazeT/Renderer/String.hs b/src/Text/BlazeT/Renderer/String.hs
index 9f0e0a0..45c4786 100644
--- a/src/Text/BlazeT/Renderer/String.hs
+++ b/src/Text/BlazeT/Renderer/String.hs
@@ -1,11 +1,10 @@
+{-# LANGUAGE RankNTypes #-}
 module Text.BlazeT.Renderer.String
     ( fromChoiceString
     , renderMarkup
     , renderHtml
   ) where
 
-import           Control.Monad
-import           Control.Monad.Identity
 import           Text.Blaze.Internal (ChoiceString)
 import qualified Text.Blaze.Renderer.String as BU
 import           Text.BlazeT
diff --git a/src/Text/BlazeT/Renderer/Text.hs b/src/Text/BlazeT/Renderer/Text.hs
index 991c81c..a595bd1 100644
--- a/src/Text/BlazeT/Renderer/Text.hs
+++ b/src/Text/BlazeT/Renderer/Text.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE RankNTypes #-}
 module Text.BlazeT.Renderer.Text
     ( renderMarkupBuilder
     , renderMarkupBuilderWith
diff --git a/src/Text/BlazeT/Renderer/Utf8.hs b/src/Text/BlazeT/Renderer/Utf8.hs
index b5fd656..2874b68 100644
--- a/src/Text/BlazeT/Renderer/Utf8.hs
+++ b/src/Text/BlazeT/Renderer/Utf8.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE RankNTypes #-}
 {-# OPTIONS_GHC -fsimpl-tick-factor=230 #-}
 
 -- the above option was not needed with