typelits-witnesses 0.1.2.0 → 0.1.3.0

raw patch · 2 files changed

+27/−7 lines, 2 filesdep ~base

Dependency ranges changed: base

Files

• src/GHC/TypeLits/List.hs +26/−6
• typelits-witnesses.cabal +1/−1

@@ -39,6 +39,7 @@   , someNatsVal   , someNatsVal'   , reifyNats+  , reifyNats'   , sameNats   -- ** Traversals   , traverseNatList@@ -199,19 +200,36 @@ -- -- Essentially a continuation-style version of 'SomeNats'. ----- For compatability with 'reifyNat', be aware that this also produces--- @'KnownNat' n@s where @n@ is negative, without complaining.+-- Be aware that this also produces @'KnownNat' n@s where @n@ is negative,+-- without complaining.  To be consistent, within the library, this+-- /should/ be called @reifyNatsPos@; however, the naming choice is for+-- consistency with 'reifyNat' from the /reflections/ package.  Use+-- 'reifyNats'' for a "safe" version. reifyNats :: [Integer] -> (forall ns. KnownNats ns => NatList ns -> r) -> r reifyNats []     f = f ØNL reifyNats (n:ns) f = reifyNat n $ \m ->                        reifyNats ns $ \ms ->                          f (m :<# ms) +-- | "Safe" version of 'reifyNats', which will only run the continuation if+-- every 'Integer' in the list is non-negative.  If not, then returns+-- the given "default" value instead.+reifyNats'+    :: [Integer]+    -> r+    -> (forall ns. KnownNats ns => NatList ns -> r)+    -> r+reifyNats' ns d f =+    case someNatsVal ns of+      Just (SomeNats ms) -> f ms+      Nothing            -> d++ -- | Like 'someNatsVal', but will also go ahead and produce 'KnownNat's -- whose integer values are negative.  It won't ever error on producing -- them, but extra care must be taken when using the produced 'SomeNat's.-someNatsVal' :: [Integer] -> SomeNats-someNatsVal' ns = reifyNats ns SomeNats+someNatsValPos :: [Integer] -> SomeNats+someNatsValPos ns = reifyNats ns SomeNats  -- | Get evidence that the two 'KnownNats' lists are actually the "same" -- list of 'Nat's (that they were instantiated with the same numbers).@@ -222,7 +240,7 @@ -- case 'sameNats' ns ms of --   Just 'Refl' -> -- in this branch, GHC recognizes that the two ['Nat']s --                  -- are the same.---   Nothing     -> -- in this branch, they aren't+--   Nothing   -> -- in this branch, they aren't -- @ sameNats     :: (KnownNats ns, KnownNats ms)@@ -380,6 +398,7 @@                           reifySymbols ns $ \ms ->                             f (m :<$ ms) + -- | Get evidence that the two 'KnownSymbols' lists are actually the "same" -- list of 'Symboles's (that they were instantiated with the same strings). --@@ -389,7 +408,7 @@ -- case 'sameSymbols' ns ms of --   Just 'Refl' -> -- in this branch, GHC recognizes that the --                  -- two ['Symbol']s are the same---   Nothing     -> -- in this branch, they aren't+--   Nothing   -> -- in this branch, they aren't -- @ sameSymbols     :: (KnownSymbols ns, KnownSymbols ms)@@ -409,3 +428,4 @@             Refl <- sameSymbol n m             Refl <- sameSymbols ns' ms'             return Refl+

@@ -1,5 +1,5 @@ name:                typelits-witnesses-version:             0.1.2.0+version:             0.1.3.0 synopsis:            Existential witnesses, singletons, and classes for operations on GHC TypeLits description:         Provides witnesses for 'KnownNat' and 'KnownSymbol'                      instances for various operations on GHC TypeLits - in