diff --git a/calculator.cabal b/calculator.cabal
--- a/calculator.cabal
+++ b/calculator.cabal
@@ -1,5 +1,5 @@
 name:                calculator
-version:             0.2.2.0
+version:             0.2.2.1
 synopsis:            A calculator repl.
 description:         A calculator repl that processes mathematical expressions.
                      Does basic arithmetic, and provides pre-defined basic mathematical functions.
@@ -33,12 +33,11 @@
                      , Calculator.Prim.Expr
                      , Calculator.Prim.Function
                      , Calculator.Prim.Statement
+                     , Calculator.Color
   -- other-extensions:    
-  build-depends:       QuickCheck >= 2.7.6 && <2.7.7
-                     , base >=4.7 && <4.8
+  build-depends:       base >=4.7 && <4.8
                      , containers >= 0.5.5.1 && <0.5.6.0
                      , haskeline >=0.7.1.0 && <0.7.2.0
-                     , mtl >= 2.2.1
                      , parsec >=3.1.7 && <3.2
   hs-source-dirs:      src/
   ghc-options:         -Wall
@@ -68,7 +67,6 @@
   build-depends:       QuickCheck >= 2.7.6 && <2.7.7
                      , base >=4.7 && <4.8
                      , containers >= 0.5.5.1 && <0.5.6.0
-                     , mtl >= 2.2.1
                      , parsec >=3.1.7 && <3.2
   ghc-options:         -Wall
   default-language:    Haskell2010
diff --git a/src/Calculator/Color.hs b/src/Calculator/Color.hs
new file mode 100644
--- /dev/null
+++ b/src/Calculator/Color.hs
@@ -0,0 +1,26 @@
+module Calculator.Color
+    ( Color (..)
+    , color
+    , bold
+    ) where
+
+--------------------------------------------------------------------------------
+
+data Color = Black | Red     | Green | Yellow
+           | Blue  | Magenta | Cyan  | White
+           | Reset
+           deriving Enum
+
+--------------------------------------------------------------------------------
+
+color :: Color -> Bool -> String -> String
+color c b s = let col = show (fromEnum c)
+                  bol = if b then "1" else "22"
+              in "\ESC[" ++ bol ++ ";3" ++ col ++ "m" ++ s ++ "\ESC[0;m"
+
+--------------------------------------------------------------------------------
+
+bold :: String -> String
+bold = color Reset True
+
+--------------------------------------------------------------------------------
diff --git a/src/Calculator/Parser/Cmd.hs b/src/Calculator/Parser/Cmd.hs
--- a/src/Calculator/Parser/Cmd.hs
+++ b/src/Calculator/Parser/Cmd.hs
@@ -1,9 +1,9 @@
 module Calculator.Parser.Cmd
     ( parseCmd
+    , parseAssignCmd
     , parseAssign
-    , parseAssign'
+    , parseFuncCmd
     , parseFunc
-    , parseFunc'
     ) where
 
 --------------------------------------------------------------------------------
@@ -30,8 +30,8 @@
 parseCmd' = parseShow
          <|> parseHelp
          <|> parseReset
-         <|> parseAssign
-         <|> parseFunc
+         <|> parseAssignCmd
+         <|> parseFuncCmd
 
 --------------------------------------------------------------------------------
 -- help -> "?" | "help"
@@ -52,13 +52,13 @@
 parseReset = string "reset" >> spaces >> return Reset
 
 --------------------------------------------------------------------------------
--- assign -> "var" id "=" expr
+-- assignCmd -> "var" id "=" expr
 
-parseAssign :: Parser Cmd
-parseAssign = string "var" >> space >> spaces >> parseAssign'
+parseAssignCmd :: Parser Cmd
+parseAssignCmd = string "var" >> space >> spaces >> parseAssign
 
-parseAssign' :: Parser Cmd
-parseAssign' = do
+parseAssign :: Parser Cmd
+parseAssign = do
   str <- parseId
   _   <- spaces
   _   <- char '='
@@ -69,11 +69,11 @@
 --------------------------------------------------------------------------------
 -- func  -> "func" id (args) "=" expr
 
-parseFunc :: Parser Cmd
-parseFunc = string "func" >> space >> spaces >> parseFunc'
+parseFuncCmd :: Parser Cmd
+parseFuncCmd = string "func" >> space >> spaces >> parseFunc
 
-parseFunc' :: Parser Cmd
-parseFunc' = do
+parseFunc :: Parser Cmd
+parseFunc = do
   ident <- try (parseId <* (spaces >> char '(' >> spaces))
   args  <- (parseId <* spaces) `sepBy` (char ',' <* spaces) <* char ')'
   _     <- spaces >> char '=' <* spaces