Repository : ssh://darcs.haskell.org//srv/darcs/packages/base On branch : master
http://hackage.haskell.org/trac/ghc/changeset/533436192c78b7d2352c9d3f5689c4f24dc0920f >--------------------------------------------------------------- commit 533436192c78b7d2352c9d3f5689c4f24dc0920f Author: Iavor S. Diatchki <[email protected]> Date: Sun Nov 11 18:23:47 2012 -0800 Declare a family for subtraction. >--------------------------------------------------------------- GHC/TypeLits.hs | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/GHC/TypeLits.hs b/GHC/TypeLits.hs index 4db4cbb..b8733ca 100644 --- a/GHC/TypeLits.hs +++ b/GHC/TypeLits.hs @@ -27,6 +27,7 @@ module GHC.TypeLits -- * Functions on type nats , type (<=), type (<=?), type (+), type (*), type (^) + , type (-) -- * Destructing type-nat singletons. , isZero, IsZero(..) @@ -106,6 +107,10 @@ type family (m :: Nat) * (n :: Nat) :: Nat -- | Exponentiation of type-level naturals. type family (m :: Nat) ^ (n :: Nat) :: Nat +-- | Subtraction of type-level naturals. +-- Note that this operation is unspecified for some inputs. +type family (m :: Nat) - (n :: Nat) :: Nat + -------------------------------------------------------------------------------- _______________________________________________ Cvs-libraries mailing list [email protected] http://www.haskell.org/mailman/listinfo/cvs-libraries
