{-# LANGUAGE Trustworthy #-} {-# LANGUAGE CPP, NoImplicitPrelude #-} ----------------------------------------------------------------------------- -- | -- Module : Data.Int -- Copyright : (c) The University of Glasgow 2001 -- License : BSD-style (see the file libraries/base/LICENSE) -- -- Maintainer : libraries@haskell.org -- Stability : experimental -- Portability : portable -- -- Signed integer types -- ----------------------------------------------------------------------------- module Data.Int ( -- * Signed integer types Int, Int8, Int16, Int32, Int64, -- * Notes -- $notes ) where #ifdef __GLASGOW_HASKELL__ import GHC.Base ( Int ) import GHC.Int ( Int8, Int16, Int32, Int64 ) #endif #ifdef __HUGS__ import Hugs.Int ( Int8, Int16, Int32, Int64 ) #endif #ifdef __NHC__ import Prelude import Prelude (Int) import NHC.FFI (Int8, Int16, Int32, Int64) import NHC.SizedTypes (Int8, Int16, Int32, Int64) -- instances of Bits #endif {- $notes * All arithmetic is performed modulo 2^n, where @n@ is the number of bits in the type. * For coercing between any two integer types, use 'Prelude.fromIntegral', which is specialized for all the common cases so should be fast enough. Coercing word types (see "Data.Word") to and from integer types preserves representation, not sign. * The rules that hold for 'Prelude.Enum' instances over a bounded type such as 'Int' (see the section of the Haskell report dealing with arithmetic sequences) also hold for the 'Prelude.Enum' instances over the various 'Int' types defined here. * Right and left shifts by amounts greater than or equal to the width of the type result in either zero or -1, depending on the sign of the value being shifted. This is contrary to the behaviour in C, which is undefined; a common interpretation is to truncate the shift count to the width of the type, for example @1 \<\< 32 == 1@ in some C implementations. -}