diff --git a/README.md b/README.md
deleted file mode 100644
--- a/README.md
+++ /dev/null
@@ -1,3 +0,0 @@
-# `Control.Dsl`: An alternative to monads
-
-See [`Control.Dsl` on Hackage](https://hackage.haskell.org/package/control-dsl/docs/Control-Dsl.html) for more information.
diff --git a/control-dsl.cabal b/control-dsl.cabal
--- a/control-dsl.cabal
+++ b/control-dsl.cabal
@@ -1,65 +1,69 @@
-cabal-version: >=1.10
-name: control-dsl
-version: 0.2.0.0
-license: BSD3
-license-file: LICENSE
-copyright: 2018 Yang Bo
-maintainer: pop.atry@gmail.com
-author: Yang Bo
-homepage: https://github.com/Atry/Control.Dsl#readme
-bug-reports: https://github.com/Atry/Control.Dsl/issues
-synopsis: An alternative to monads
-description:
-    This \"control-dsl\" package is a toolkit to create extensible Domain Specific Languages in @do@-notation.
-    .
-    See "Control.Dsl" for more information.
-category: Control, DSL, Effect, General, Language, Mutable State, IO, Polymorphism
-build-type: Simple
+-- This file has been generated from package.yaml by hpack version 0.28.2.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: fc82e777d97572d734e72a654633c712086ba0638376cc070e09e2e22c4831aa
+
+name:           control-dsl
+version:        0.2.0.1
+synopsis:       An alternative to monads
+description:    This \"control-dsl\" package is a toolkit to create extensible Domain Specific Languages in @do@-notation.
+                .
+                See "Control.Dsl" for more information.
+category:       Control, DSL, Effect, General, Language, Mutable State, IO, Polymorphism
+homepage:       https://github.com/Atry/Control.Dsl#readme
+bug-reports:    https://github.com/Atry/Control.Dsl/issues
+author:         Yang Bo
+maintainer:     pop.atry@gmail.com
+copyright:      2018 Yang Bo
+license:        BSD3
+license-file:   LICENSE
+build-type:     Simple
+cabal-version:  >= 1.10
 extra-source-files:
     ChangeLog.md
-    README.md
 
 source-repository head
-    type: git
-    location: https://github.com/Atry/Control.Dsl
+  type: git
+  location: https://github.com/Atry/Control.Dsl
 
 library
-    exposed-modules:
-        Control.Dsl
-        Control.Dsl.Cont
-        Control.Dsl.Empty
-        Control.Dsl.Monadic
-        Control.Dsl.PolyCont
-        Control.Dsl.Return
-        Control.Dsl.Shift
-        Control.Dsl.State
-        Control.Dsl.State.Get
-        Control.Dsl.State.Put
-        Control.Dsl.Yield
-    hs-source-dirs: src
-    other-modules:
-        Control.Dsl.Dsl
-        Control.Dsl.State.State
-    default-language: Haskell2010
-    other-extensions: RebindableSyntax MultiParamTypeClasses
-                      TypeOperators FlexibleInstances FlexibleContexts
-                      UndecidableInstances RankNTypes GADTs
-    build-depends:
-        base >=4.8 && <5
+  exposed-modules:
+      Control.Dsl
+      Control.Dsl.Cont
+      Control.Dsl.Empty
+      Control.Dsl.Monadic
+      Control.Dsl.PolyCont
+      Control.Dsl.Return
+      Control.Dsl.Shift
+      Control.Dsl.State
+      Control.Dsl.State.Get
+      Control.Dsl.State.Put
+      Control.Dsl.Yield
+  other-modules:
+      Control.Dsl.Dsl
+      Control.Dsl.State.State
+  hs-source-dirs:
+      src
+  other-extensions: RebindableSyntax MultiParamTypeClasses TypeOperators FlexibleInstances FlexibleContexts UndecidableInstances RankNTypes GADTs
+  build-depends:
+      base >=4.8 && <5
+  default-language: Haskell2010
 
 test-suite doctests
-    type: exitcode-stdio-1.0
-    main-is: doctest-driver.hs
-    hs-source-dirs: test
-    other-modules:
-        Paths_control_dsl
-    default-language: Haskell2010
-    other-extensions: TypeApplications
-    ghc-options: -threaded -rtsopts -with-rtsopts=-N
-    build-depends:
-        base >=4.8 && <5,
-        containers >=0.5.11.0 && <0.6,
-        control-dsl -any,
-        doctest >=0.16.0.1 && <0.17,
-        doctest-discover >=0.1.0.9 && <0.2,
-        temporary ==1.3.*
+  type: exitcode-stdio-1.0
+  main-is: doctest-driver.hs
+  other-modules:
+      Paths_control_dsl
+  hs-source-dirs:
+      test
+  other-extensions: TypeApplications
+  ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.8 && <5
+    , containers
+    , control-dsl
+    , doctest
+    , doctest-discover
+    , temporary
+  default-language: Haskell2010
diff --git a/src/Control/Dsl.hs b/src/Control/Dsl.hs
--- a/src/Control/Dsl.hs
+++ b/src/Control/Dsl.hs
@@ -8,7 +8,7 @@
 
 A DSL @do@ block contains heterogeneous statements from different vendors.
 A statement can be defined as a GADT,
-interpreted by a 'Dsl' type class instance, either effectful or purely.
+interpreted by a 'Dsl' type class instance, either effectfully or purely.
 
 A DSL @do@ block is abstract.
 When creating the block, the type class requirements is automatically inferred.
@@ -70,7 +70,7 @@
 
 === Creating a pure interpreter
 
-The type of @r@ varies from different 'Contro.Dsl.PolyCont.PolyCont' instances.
+The type @r@ varies from different 'Contro.Dsl.PolyCont.PolyCont' instances.
 By defining 'Contro.Dsl.PolyCont.PolyCont' instances for @PureInterpreter@,
 you can make @r@ be a @PureInterpreter@:
 
diff --git a/src/Control/Dsl/Cont.hs b/src/Control/Dsl/Cont.hs
--- a/src/Control/Dsl/Cont.hs
+++ b/src/Control/Dsl/Cont.hs
@@ -41,11 +41,11 @@
 when True k = k
 when False _ = Cont ($ ())
 
-unless True _ = Cont $ \f -> f ()
-unless False (Cont k) = Cont k
+unless True _ = Cont ($ ())
+unless False k = k
 
-guard True = Cont $ \f -> f ()
-guard False = Cont $ \f -> empty
+guard True = Cont ($ ())
+guard False = Cont (const empty)
 
 instance {-# OVERLAPS #-} PolyCont k r a => PolyCont k (Cont r a') a where
   runPolyCont k f = Cont $ \g -> runPolyCont k $ \a -> runCont (f a) g
diff --git a/src/Control/Dsl/Dsl.hs b/src/Control/Dsl/Dsl.hs
--- a/src/Control/Dsl/Dsl.hs
+++ b/src/Control/Dsl/Dsl.hs
@@ -14,9 +14,12 @@
 
 == Allowed statements in DSL @do@ blocks
 
-A statement in a DSL @do@ block is a delimited continuation,
-which can be a GADT keyword, a control flow operator,
-or the final result:
+Statements in a DSL @do@ block is a delimited continuation
+(except the last statement),
+which can be a GADT keyword, a control flow operator.
+
+The last statement is the final result of the @do@ block,
+or the /answer type/ of other delimited continuation statements.
 
 +-------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------------------------+----------------------------------------------------------------------------------------------+
 |                   |                                                                                                Keywords                                                                                               |          Control flow operators         |                                            Results                                           |