diff --git a/Makefile b/Makefile
--- a/Makefile
+++ b/Makefile
@@ -31,6 +31,7 @@
 	$(foreach t,$(TESTS1),cd Test && $(GHC) -F -pgmF interpol $(t)${\n})
 	$(foreach t,$(TESTS2),cd Test && $(GHC) $(t)${\n})
 	$(foreach t,$(TESTS1) $(TESTS2),cd Test && [ "`./$(t)`" = "I have 23 apples." ]${\n})
+	runhaskell Test/Unit.hs
 
 dist/setup-config: interpol.cabal
 	cabal configure
diff --git a/NEWS.md b/NEWS.md
new file mode 100644
--- /dev/null
+++ b/NEWS.md
@@ -0,0 +1,15 @@
+News
+====
+
+v0.2.2
+------
+
+Bug-fix release for `v0.2.1`.  All API changes are backwards
+compatible: the ToString type-class is exported.  Fixes the
+interpolation of `Char`s (thank you [nh2](https://github.com/nh2)).
+
+v0.2.1
+------
+
+Bug-fix release for `v0.2.0`.  It does not change the API in any way,
+but adds a few more tests and some more documentation.
diff --git a/Test/Unit.hs b/Test/Unit.hs
new file mode 100644
--- /dev/null
+++ b/Test/Unit.hs
@@ -0,0 +1,30 @@
+module Main where
+
+import System.Exit ( exitFailure )
+import Test.HUnit
+import Text.Interpol
+
+main :: IO ()
+main = do
+  runCounts <- runTestTT $ test [ toStringTests ]
+  if failures runCounts + errors runCounts == 0
+    then
+      putStrLn "All unit tests pass :)"
+    else do
+      putStrLn "Failures or errors occured :'("
+      exitFailure
+
+toStringTests :: Test
+toStringTests =
+    test [ "string" ~: TestCase $ do
+             assertEqual "" "I have apples" ("I " ^-^ "have " ^-^ "apples")
+         , "char" ~: TestCase $ do
+             assertEqual "" "Triple 'X'" ("Triple " ^-^ 'X')
+         , "number" ~: TestCase $ do
+             assertEqual "" "Am 21 years old" ("Am " ^-^ (21 :: Int) ^-^
+                                               " years old")
+         , "first" ~: TestCase $ do
+             assertEqual "" "21 is my age" ((21 :: Int) ^-^ " is my age")
+         , "utf" ~: TestCase $ do
+             assertEqual "" "Umlaut: 'ü'" ("Umlaut: " ^-^ 'ü')
+         ]
diff --git a/Text/Interpol.hs b/Text/Interpol.hs
--- a/Text/Interpol.hs
+++ b/Text/Interpol.hs
@@ -3,6 +3,8 @@
 -- | Support module for the @interpol@ preprocessor.
 module Text.Interpol (
         (^-^)
+      , interpol
+      , ToString
     ) where
 
 infixl 3 ^-^
@@ -16,14 +18,22 @@
 --   x ^-^ y = x ++ y
 --   x ^-^ y = x ++ show y
 -- @
-(^-^) :: Interpol a => String -> a -> String
+--
+-- For all intents and purposes, the 'ToString' type-class is a
+-- wrapper around 'Show', so any type that has an instance for 'Show'
+-- will also have an instance for 'Interpol'.
+(^-^), interpol :: (ToString a, ToString b) => a -> b -> String
 (^-^) = interpol
+interpol a b = toString a ++ toString b
 
-class Interpol a where
-    interpol :: String -> a -> String
+class ToString a where
+    toString :: a -> String
 
-instance Interpol [Char] where
-    interpol s x = s ++ x
+instance ToString [Char] where
+    toString = id
 
-instance Show a => Interpol a where
-    interpol s x = s ++ show x
+instance ToString Char where
+    toString c = '\'' : c : "'"
+
+instance Show a => ToString a where
+    toString = show
diff --git a/interpol.cabal b/interpol.cabal
--- a/interpol.cabal
+++ b/interpol.cabal
@@ -1,5 +1,5 @@
 Name:           interpol
-Version:        0.2.1
+Version:        0.2.2
 Cabal-Version:  >= 1.6
 License:        GPL-3
 License-File:   LICENSE
@@ -8,10 +8,13 @@
 Maintainer:     scvalex@gmail.com
 Homepage:       https://github.com/scvalex/interpol
 Category:       Source-tools, Language
-Synopsis:       GHC preprocessor to enable variable interpolation in strings
+Synopsis:       GHC preprocessor and library to enable variable interpolation in strings
 Build-type:     Simple
-Description:    This preprocessor enables variable interpolation in strings.
-                See the README.md file for details.
+Description:
+        This preprocessor enables variable interpolation in strings.
+        Alternatively, the library may be used.
+        .
+        See the README.md file for details.
 
 Extra-source-files:     Makefile,
                         Test/JustShow.hs,
@@ -22,9 +25,10 @@
                         Test/PureString.hs,
                         Test/Simple.hs,
                         Test/Standalone.hs,
-                        Test/String.hs
+                        Test/String.hs,
+                        Test/Unit.hs
 
-Data-files:             README.md
+Data-files:             README.md, NEWS.md
 
 Source-repository head
   Type:                 git