[#100] Add bug

CHANGES.md

@@ -1,3 +1,9 @@
+1.0.1
+=====
+
+* [#100](https:/serokell/universum/issues/100):
+ Add `bug` function = `impureThrow`.
+
 1.0.0
 =====
 

src/Universum/Exception.hs

@@ -1,4 +1,5 @@
 {-# LANGUAGE CPP #-}
+{-# LANGUAGE ImplicitParams #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE Safe #-}
 
@@ -7,6 +8,10 @@
 
 module Universum.Exception
  ( module Control.Exception.Safe
+#if ( __GLASGOW_HASKELL__ >= 800 )
+ , Bug (..)
+ , bug
+#endif
  , note
  ) where
 
@@ -19,6 +24,25 @@ import Control.Applicative (Applicative (pure))
 import Control.Monad.Except (MonadError, throwError)
 import Data.Maybe (Maybe, maybe)
 
+#if ( __GLASGOW_HASKELL__ >= 800 )
+import GHC.Show (Show)
+import GHC.Stack (CallStack, HasCallStack)
+
+import qualified Control.Exception.Safe as Safe (impureThrow, toException)
+
+-- | Type that represents exceptions used in cases when a particular codepath
+-- is not meant to be ever executed, but happens to be executed anyway.
+data Bug = Bug SomeException CallStack
+ deriving (Show)
+
+instance Exception Bug
+
+-- | Generate a pure value which, when forced, will synchronously
+-- throw the exception wrapped into 'Bug' data type.
+bug :: (HasCallStack, Exception e) => e -> a
+bug e = Safe.impureThrow (Bug (Safe.toException e) ?callStack)
+#endif
+
 -- To suppress redundant applicative constraint warning on GHC 8.0
 -- | Throws error for 'Maybe' if 'Data.Maybe.Nothing' is given.
 -- Operates over 'MonadError'.

universum.cabal

@@ -1,5 +1,5 @@
 name: universum
-version: 1.0.0
+version: 1.0.1
 synopsis: Custom prelude used in Serokell
 description: Custom prelude used in Serokell
 homepage: https:/serokell/universum