2 files changed, 13 insertions, 5 deletions
diff --git a/src/Language/GraphQL/AST/Encoder.hs b/src/Language/GraphQL/AST/Encoder.hs
index 0d448df..54967ea 100644
--- a/src/Language/GraphQL/AST/Encoder.hs
+++ b/src/Language/GraphQL/AST/Encoder.hs
@@ -11,6 +11,7 @@ module Language.GraphQL.AST.Encoder
     , directive
     , document
     , minified
+    , operationType
     , pretty
     , type'
     , value
@@ -34,7 +35,7 @@ import qualified Language.GraphQL.AST.Document as Full
 --   Use 'pretty' or 'minified' to construct the formatter.
 data Formatter
     = Minified
-    | Pretty Word
+    | Pretty !Word
 
 -- | Constructs a formatter for pretty printing.
 pretty :: Formatter
@@ -101,7 +102,7 @@ variableDefinition formatter variableDefinition' =
      in variable variableName
     <> eitherFormat formatter ": " ":"
     <> type' variableType
-    <> maybe mempty (defaultValue formatter) (Full.node <$> defaultValue')
+    <> maybe mempty (defaultValue formatter . Full.node) defaultValue'
 
 defaultValue :: Formatter -> Full.ConstValue -> Lazy.Text
 defaultValue formatter val
@@ -294,6 +295,12 @@ nonNullType :: Full.NonNullType -> Lazy.Text
 nonNullType (Full.NonNullTypeNamed x) = Lazy.Text.fromStrict x <> "!"
 nonNullType (Full.NonNullTypeList x) = listType x <> "!"
 
+-- | Produces lowercase operation type: query, mutation or subscription.
+operationType :: Formatter -> Full.OperationType -> Lazy.Text
+operationType _formatter Full.Query = "query"
+operationType _formatter Full.Mutation = "mutation"
+operationType _formatter Full.Subscription = "subscription"
+
 -- * Internal
 
 between :: Char -> Char -> Lazy.Text -> Lazy.Text
diff --git a/src/Language/GraphQL/AST/Lexer.hs b/src/Language/GraphQL/AST/Lexer.hs
index ecefaf6..ab1f36f 100644
--- a/src/Language/GraphQL/AST/Lexer.hs
+++ b/src/Language/GraphQL/AST/Lexer.hs
@@ -58,6 +58,7 @@ import qualified Text.Megaparsec.Char.Lexer as Lexer
 import Data.Text (Text)
 import qualified Data.Text as T
 import qualified Data.Text.Lazy as TL
+import Control.Monad (void)
 
 -- | Standard parser.
 -- Accepts the type of the parsed token.
@@ -93,7 +94,7 @@ dollar = symbol "$"
 
 -- | Parser for "@".
 at :: Parser ()
-at = symbol "@" >> pure ()
+at = void $ symbol "@"
 
 -- | Parser for "&".
 amp :: Parser T.Text
@@ -101,7 +102,7 @@ amp = symbol "&"
 
 -- | Parser for ":".
 colon :: Parser ()
-colon = symbol ":" >> pure ()
+colon = void $ symbol ":"
 
 -- | Parser for "=".
 equals :: Parser T.Text
@@ -220,7 +221,7 @@ escapeSequence = do
 
 -- | Parser for the "Byte Order Mark".
 unicodeBOM :: Parser ()
-unicodeBOM = optional (char '\xfeff') >> pure ()
+unicodeBOM = void $ optional $ char '\xfeff'
 
 -- | Parses "extend" followed by a 'symbol'. It is used by schema extensions.
 extend :: forall a. Text -> String -> NonEmpty (Parser a) -> Parser a