From 9b5a564f3c151c699a6ee16c7e0dfc9564fcc1f8 Mon Sep 17 00:00:00 2001
From: Alex Mason <Alex.Mason@data61.csiro.au>
Date: Fri, 2 Sep 2016 23:14:45 +1000
Subject: [PATCH] Remove dependency on bytestring-conversion

---
 servant/servant.cabal                      |  1 -
 servant/src/Servant/API/ResponseHeaders.hs | 13 ++++++-------
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/servant/servant.cabal b/servant/servant.cabal
index 0f308995..56a2cc6e 100644
--- a/servant/servant.cabal
+++ b/servant/servant.cabal
@@ -54,7 +54,6 @@ library
     , aeson                 >= 0.7  && < 1.1
     , attoparsec            >= 0.12 && < 0.14
     , bytestring            >= 0.10 && < 0.11
-    , bytestring-conversion >= 0.3  && < 0.4
     , case-insensitive      >= 1.2  && < 1.3
     , http-api-data         >= 0.1  && < 0.3
     , http-media            >= 0.4  && < 0.7
diff --git a/servant/src/Servant/API/ResponseHeaders.hs b/servant/src/Servant/API/ResponseHeaders.hs
index d70f78b5..1ddba9d0 100644
--- a/servant/src/Servant/API/ResponseHeaders.hs
+++ b/servant/src/Servant/API/ResponseHeaders.hs
@@ -31,9 +31,8 @@ module Servant.API.ResponseHeaders
     ) where
 
 import           Data.ByteString.Char8       as BS (pack, unlines, init)
-import           Data.ByteString.Conversion  (--ToByteString, toByteString',
-                                              FromByteString, fromByteString)
-import Web.HttpApiData (ToHttpApiData,toHeader)
+import           Web.HttpApiData             (ToHttpApiData,toHeader
+                                             ,FromHttpApiData,parseHeader)
 import qualified Data.CaseInsensitive        as CI
 import           Data.Proxy
 import           GHC.TypeLits                (KnownSymbol, symbolVal)
@@ -69,17 +68,17 @@ class BuildHeadersTo hs where
 instance OVERLAPPING_ BuildHeadersTo '[] where
     buildHeadersTo _ = HNil
 
-instance OVERLAPPABLE_ ( FromByteString v, BuildHeadersTo xs, KnownSymbol h )
+instance OVERLAPPABLE_ ( FromHttpApiData v, BuildHeadersTo xs, KnownSymbol h )
          => BuildHeadersTo ((Header h v) ': xs) where
     buildHeadersTo headers =
       let wantedHeader = CI.mk . pack $ symbolVal (Proxy :: Proxy h)
           matching = snd <$> filter (\(h, _) -> h == wantedHeader) headers
       in case matching of
         [] -> MissingHeader `HCons` buildHeadersTo headers
-        xs -> case fromByteString (BS.init $ BS.unlines xs) of
-          Nothing -> UndecodableHeader (BS.init $ BS.unlines xs)
+        xs -> case parseHeader (BS.init $ BS.unlines xs) of
+          Left _err -> UndecodableHeader (BS.init $ BS.unlines xs)
              `HCons` buildHeadersTo headers
-          Just h   -> Header h `HCons` buildHeadersTo headers
+          Right h   -> Header h `HCons` buildHeadersTo headers
 
 -- * Getting