diff --git a/character-cases.cabal b/character-cases.cabal
--- a/character-cases.cabal
+++ b/character-cases.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 9ae64163844840cb8871abca02785f7de8a0e19cf7b1793390a33b068ae1a73e
+-- hash: 05975857105ecf13977f06dd3fc331dbd0c2c63a6c69bb63e94683d1949baa4c
 
 name:           character-cases
-version:        0.1.0.5
+version:        0.1.0.6
 synopsis:       Exposes subspecies types of Char. And naming cases.
 description:    e.g. meaning of [a-z], [A-Z], [0-9], PascalCase, camelCase, and snake_case. Please see https://github.com/aiya000/hs-character-cases#README.md
 category:       Simple
@@ -38,7 +38,6 @@
   build-depends:
       base >=4.7 && <5
     , containers
-    , here
     , megaparsec
     , prettyprinter
     , template-haskell
@@ -62,7 +61,6 @@
     , base >=4.7 && <5
     , containers
     , doctest
-    , here
     , megaparsec
     , prettyprinter
     , template-haskell
diff --git a/src/Data/Char/Cases.hs b/src/Data/Char/Cases.hs
--- a/src/Data/Char/Cases.hs
+++ b/src/Data/Char/Cases.hs
@@ -56,7 +56,6 @@
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as Map
 import Data.Maybe (fromJust)
-import Data.String.Here (i)
 import Data.Tuple (swap)
 import Language.Haskell.TH
 import Language.Haskell.TH.Quote (QuasiQuoter(..))
@@ -111,13 +110,13 @@
     expQ [] = fail "alphaNumCharQ required a Char, but nothign is specified."
 
     expQ (x : []) = case charToAlphaNum x of
-      Nothing -> fail [i|'${x}' is not an AlphaNumChar.|]
+      Nothing -> fail $ show x <> " is not an AlphaNumChar."
       Just (AlphaNumAlpha _) ->
         (ConE (mkName "AlphaNumAlpha") `AppE`) <$> (quoteExp alphaCharQ) [x]
       Just (AlphaNumDigit _) ->
         (ConE (mkName "AlphaNumDigit") `AppE`) <$> (quoteExp digitCharQ) [x]
 
-    expQ xs@(_ : _) = fail [i|alphaNumCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "alphaNumCharQ required a Char, but a String is specified: " <> xs
 
 
 -- | '[A-Za-z]'
@@ -150,13 +149,13 @@
     expQ [] = fail "alphaCharQ required a Char, but nothign is specified."
 
     expQ (x : []) = case charToAlpha x of
-      Nothing -> fail [i|'${x}' is not an AlphaChar.|]
+      Nothing -> fail $ show x <> " is not an AlphaChar."
       Just (AlphaLower _) ->
         (ConE (mkName "AlphaLower") `AppE`) <$> (quoteExp lowerCharQ) [x]
       Just (AlphaUpper _) ->
         (ConE (mkName "AlphaUpper") `AppE`) <$> (quoteExp upperCharQ) [x]
 
-    expQ xs@(_ : _) = fail [i|alphaCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "alphaCharQ required a Char, but a String is specified: " <> xs
 
 
 -- | '[A-Z]'
@@ -211,10 +210,10 @@
     expQ [] = fail "upperCharQ required a Char, but nothign is specified."
 
     expQ (x : []) = case charToUpper x of
-      Nothing -> fail [i|'${x}' is not an UpperChar.|]
+      Nothing -> fail $ show x <> " is not an UpperChar."
       Just z -> conE . mkName $ show z
 
-    expQ xs@(_ : _) = fail [i|upperCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "upperCharQ required a Char, but a String is specified: " <> xs
 
 
 -- | '[a-z]'
@@ -269,10 +268,10 @@
     expQ [] = fail "lowerCharQ required a Char, but nothign is specified."
 
     expQ (x : []) = case charToLower x of
-      Nothing -> fail [i|'${x}' is not a LowerChar.|]
+      Nothing -> fail $ show x <> " is not a LowerChar."
       Just z -> conE . mkName $ show z
 
-    expQ xs@(_ : _) = fail [i|lowerCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "lowerCharQ required a Char, but a String is specified: " <> xs
 
 
 -- | '[0-9]'
@@ -331,16 +330,16 @@
     expQ [] = fail "digitCharQ required a Char, but nothign is specified."
 
     expQ (x : []) = case charToDigit x of
-      Nothing -> fail [i|'${x}' is not a DigitChar.|]
+      Nothing -> fail $ show x <> " is not a DigitChar."
       Just z -> conE . mkName $ show z
 
-    expQ xs@(_ : _) = fail [i|digitCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "digitCharQ required a Char, but a String is specified: " <> xs
 
 
 -- |
 -- '[a-zA-Z0-9_]'
 --
--- Please see 'Snake'.
+-- Please see 'Data.String.Cases.Snake'.
 data SnakeChar = SnakeUnderscore -- ^ _
                | SnakeAlphaNum AlphaNumChar -- ^ [a-zA-Z0-9]
   deriving (Show, Eq)
@@ -384,19 +383,19 @@
     expQ [] = fail "snakeCharQ required a Char, but nothign is specified."
 
     expQ (x : []) = case charToSnake x of
-      Nothing -> fail [i|'${x}' is not a SnakeChar.|]
+      Nothing -> fail $ show x <> " is not a SnakeChar."
       Just SnakeUnderscore ->
         conE $ mkName "SnakeUnderscore"
       Just (SnakeAlphaNum _) ->
         (ConE (mkName "SnakeAlphaNum") `AppE`) <$> (quoteExp alphaNumCharQ) [x]
 
-    expQ xs@(_ : _) = fail [i|snakeCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "snakeCharQ required a Char, but a String is specified: " <> xs
 
 
 -- |
 -- '[a-zA-Z_]'
 --
--- Please see 'Snake'.
+-- Please see 'Data.String.Cases.Snake'.
 data SnakeHeadChar = SnakeHeadUnderscore
                    | SnakeHeadAlpha AlphaChar
   deriving (Show, Eq)
@@ -437,19 +436,19 @@
     expQ [] = fail "snakeHeadCharQ required a Char, but nothign is specified."
 
     expQ (x : []) = case charToSnakeHead x of
-      Nothing -> fail [i|'${x}' is not a SnakeHeadChar.|]
+      Nothing -> fail $ show x <> " is not a SnakeHeadChar."
       Just SnakeHeadUnderscore ->
         conE $ mkName "SnakeHeadUnderscore"
       Just (SnakeHeadAlpha _) ->
         (ConE (mkName "SnakeHeadAlpha") `AppE`) <$> (quoteExp alphaCharQ) [x]
 
-    expQ xs@(_ : _) = fail [i|snakeHeadCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "snakeHeadCharQ required a Char, but a String is specified: " <> xs
 
 
 -- |
 -- '[A-Z_]'
 --
--- Please sese 'UpperSnake'.
+-- Please sese 'Data.String.Cases.UpperSnake'.
 data UpperSnakeHeadChar = UpperSnakeHeadUnderscore -- ^ _
                         | UpperSnakeHeadUpper UpperChar -- ^ [A-Z]
   deriving (Show, Eq)
@@ -485,19 +484,19 @@
 
     expQ (x : []) = case charToUpperSnakeHead x of
       Nothing ->
-        fail [i|'${x}' is not a UpperSnakeHeadChar.|]
+        fail $ show x <> " is not a UpperSnakeHeadChar."
       Just UpperSnakeHeadUnderscore ->
         conE $ mkName "UpperSnakeHeadUnderscore"
       Just (UpperSnakeHeadUpper _) ->
         (ConE (mkName "UpperSnakeHeadUpper") `AppE`) <$> (quoteExp upperCharQ) [x]
 
-    expQ xs@(_ : _) = fail [i|upperSnakeHeadCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "upperSnakeHeadCharQ required a Char, but a String is specified: " <> xs
 
 
 -- |
 -- '[A-Z0-9_]'
 --
--- Please see 'Snake'.
+-- Please see 'Data.String.Cases.UpperSnake'.
 data UpperSnakeChar = UpperSnakeUnderscore -- ^ _
                     | UpperSnakeUpper UpperChar -- ^ [A-Z]
                     | UpperSnakeDigit DigitChar  -- ^ [0-9]
@@ -539,7 +538,7 @@
 
     expQ (x : []) = case charToUpperSnake x of
       Nothing ->
-        fail [i|'${x}' is not a UpperSnakeChar.|]
+        fail $ show x <> " is not a UpperSnakeChar."
       Just UpperSnakeUnderscore ->
         conE $ mkName "UpperSnakeUnderscore"
       Just (UpperSnakeUpper _) ->
@@ -547,4 +546,4 @@
       Just (UpperSnakeDigit _) ->
         (ConE (mkName "UpperSnakeDigit") `AppE`) <$> (quoteExp digitCharQ) [x]
 
-    expQ xs@(_ : _) = fail [i|upperSnakeCharQ required a Char, but a String is specified: ${xs}|]
+    expQ xs@(_ : _) = fail $ "upperSnakeCharQ required a Char, but a String is specified: " <> xs
diff --git a/src/Data/String/Cases.hs b/src/Data/String/Cases.hs
--- a/src/Data/String/Cases.hs
+++ b/src/Data/String/Cases.hs
@@ -157,7 +157,7 @@
 
 -- |
 -- Simular to 'nonEmptyQ',
--- but naming outsides of 'Snake' will be rejected.
+-- but naming outsides of 'Data.String.Cases.Snake' will be rejected.
 --
 -- >>> [snakeQ|foo_bar|]
 -- Snake (SnakeHeadAlpha (AlphaLower F_)) [SnakeAlphaNum (AlphaNumAlpha (AlphaLower O_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower O_)),SnakeUnderscore,SnakeAlphaNum (AlphaNumAlpha (AlphaLower B_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower A_)),SnakeAlphaNum (AlphaNumAlpha (AlphaLower R_))]
@@ -183,7 +183,7 @@
       pure $ ConE (mkName "Snake") `AppE` z `AppE` ListE zs
 
 
--- | A kind of Snake. "[A-Z_][A-Z0-9_]*"
+-- | A kind of 'Data.String.Cases'. @[A-Z_][A-Z0-9_]*@
 data UpperSnake = UpperSnake UpperSnakeHeadChar [UpperSnakeChar]
   deriving (Show, Eq)
 
