Merge branch 'master' into plugin

ChangeLog.md

@@ -1,8 +1,17 @@
 # Changelog for polysemy
 
+## 0.1.2.0 (2019-04-26)
+
+- `runInputAsReader`, `runTraceAsOutput` and `runOutputAsWriter` have more
+    generalized types
+- Added `runStateInIO`
+- Added `runOutputAsTrace`
+- Added `Members` (thanks to @TheMatten)
+
+
 ## 0.1.1.0 (2019-04-14)
 
-- Added 'runIO' interpretation (thanks to @adamConnerSax)
+- Added `runIO` interpretation (thanks to @adamConnerSax)
 - Minor documentation fixes
 
 
@@ -12,7 +21,3 @@
 
 ## Unreleased changes
 
-- `runInputAsReader`, `runTraceAsOutput` and `runOutputAsWriter` have more
-    generalized types
-- Added `runStateInIO`
-- Added `runOutputAsTrace`

package.yaml

@@ -1,5 +1,5 @@
 name:                polysemy
-version:             0.1.1.0
+version:             0.1.2.0
 github:              "isovector/polysemy"
 license:             BSD3
 author:              "Sandy Maguire"

polysemy.cabal

@@ -4,10 +4,10 @@ cabal-version: 1.12
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: a746514de75e4e865e1cecad7b39efb038ae28b0024a9285dcd3ed80606f822f
+-- hash: e7d506fb8346095c09f6efd4fec48a435a2e85513956419a807073dea1fe0274
 
 name:           polysemy
-version:        0.1.1.0
+version:        0.1.2.0
 synopsis:       Higher-order, low-boilerplate, zero-cost free monads.
 description:    Please see the README on GitHub at <https://github.com/isovector/polysemy#readme>
 category:       Language

src/Polysemy.hs

@@ -2,6 +2,7 @@ module Polysemy
   ( -- * Core Types
     Sem ()
   , Member
+  , Members
 
   -- * Running Sem
   , run
@@ -110,9 +111,6 @@ module Polysemy
   , runT
   , bindT
 
-  -- * Reexports
-  , Typeable
-
   -- * Deprecated Names
   -- | The following exports are deprecated, and are exposed only for
   -- backwards compatability reasons. They will be removed in the next major
@@ -123,7 +121,6 @@ module Polysemy
   , makeSemantic_
   ) where
 
-import Data.Typeable
 import Polysemy.Internal
 import Polysemy.Internal.Combinators
 import Polysemy.Internal.TH.Effect

src/Polysemy/Internal.hs

@@ -6,6 +6,7 @@
 module Polysemy.Internal
   ( Sem (..)
   , Member
+  , Members
   , send
   , sendM
   , run
@@ -23,6 +24,7 @@ import Control.Applicative
 import Control.Monad.Fix
 import Control.Monad.IO.Class
 import Data.Functor.Identity
+import Data.Kind
 import Polysemy.Internal.Effect
 import Polysemy.Internal.Fixpoint
 import Polysemy.Internal.Lift
@@ -129,6 +131,34 @@ newtype Sem r a = Sem
   }
 
 
+------------------------------------------------------------------------------
+-- | Makes constraints of functions that use multiple effects shorter by
+-- translating single list of effects into multiple 'Member' constraints:
+--
+-- @
+-- foo :: 'Members' \'[ 'Polysemy.Output.Output' Int
+--                 , 'Polysemy.Output.Output' Bool
+--                 , 'Polysemy.State' String
+--                 ] r
+--     => 'Sem' r ()
+-- @
+--
+-- translates into:
+--
+-- @
+-- foo :: ( 'Member' ('Polysemy.Output.Output' Int) r
+--        , 'Member' ('Polysemy.Output.Output' Bool) r
+--        , 'Member' ('Polysemy.State' String) r
+--        )
+--     => 'Sem' r ()
+-- @
+--
+-- @since 0.1.2.0
+type family Members es r :: Constraint where
+  Members '[]       r = ()
+  Members (e ': es) r = (Member e r, Members es r)
+
+
 ------------------------------------------------------------------------------
 -- | Like 'runSem' but flipped for better ergonomics sometimes.
 usingSem