Move gql to Language.GraphQL.TH

2 files changed, 50 insertions, 0 deletions

diff --git a/src/Language/GraphQL/Class.hs b/src/Language/GraphQL/Class.hs
index 6e8b080..67ae695 100644
--- a/src/Language/GraphQL/Class.hs
+++ b/src/Language/GraphQL/Class.hs
@@ -485,6 +485,7 @@ stripIndentation code = reverse
 
 -- | Removes leading and trailing newlines. Indentation of the first line is
 -- removed from each line of the string.
+{-# DEPRECATED gql "Use Language.GraphQL.TH.gql instead" #-}
 gql :: QuasiQuoter
 gql = QuasiQuoter
     { quoteExp = pure . LitE . StringL . stripIndentation
diff --git a/src/Language/GraphQL/TH.hs b/src/Language/GraphQL/TH.hs
new file mode 100644
index 0000000..6e20586
--- /dev/null
+++ b/src/Language/GraphQL/TH.hs
@@ -0,0 +1,49 @@
+{- This Source Code Form is subject to the terms of the Mozilla Public License,
+   v. 2.0. If a copy of the MPL was not distributed with this file, You can
+   obtain one at https://mozilla.org/MPL/2.0/. -}
+
+module Language.GraphQL.TH
+    ( gql
+    ) where
+
+import Language.Haskell.TH
+    ( Exp(..)
+    , Lit(..)
+    )
+import Language.Haskell.TH.Quote (QuasiQuoter(..))
+
+stripIndentation :: String -> String
+stripIndentation code = reverse
+    $ dropWhile isLineBreak
+    $ reverse
+    $ unlines
+    $ indent spaces <$> lines' withoutLeadingNewlines
+  where
+    indent 0 xs = xs
+    indent count (' ' : xs) = indent (count - 1) xs
+    indent _ xs = xs
+    withoutLeadingNewlines = dropWhile isLineBreak code
+    spaces = length $ takeWhile (== ' ') withoutLeadingNewlines
+    lines' "" = []
+    lines' string =
+        let (line, rest) = break isLineBreak string
+            reminder =
+                case rest of
+                    [] -> []
+                    '\r' : '\n' : strippedString -> lines' strippedString
+                    _ : strippedString -> lines' strippedString
+         in line : reminder
+    isLineBreak = flip any ['\n', '\r'] . (==)
+
+-- | Removes leading and trailing newlines. Indentation of the first line is
+-- removed from each line of the string.
+gql :: QuasiQuoter
+gql = QuasiQuoter
+    { quoteExp = pure . LitE . StringL . stripIndentation
+    , quotePat = const
+        $ fail "Illegal gql QuasiQuote (allowed as expression only, used as a pattern)"
+    , quoteType = const
+        $ fail "Illegal gql QuasiQuote (allowed as expression only, used as a type)"
+    , quoteDec = const
+        $ fail "Illegal gql QuasiQuote (allowed as expression only, used as a declaration)"
+    }