Safe Haskell | Safe |
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# Unsigned integral types

This module provides unsigned integer types of unspecified width (`Word`

)
and fixed widths (`Word8`

, `Word16`

, `Word32`

and `Word64`

). 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
`fromIntegral`

. Coercing word types to and from integer
types preserves representation, not sign.

The rules that hold for `Enum`

instances over a bounded type
such as `Int`

(see the section of the Haskell language report dealing
with arithmetic sequences) also hold for the `Enum`

instances
over the various `Word`

types defined here.

Right and left shifts by amounts greater than or equal to the width of
the type result in a zero result. 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.

data Word

data Word8

8-bit unsigned integer type

data Word16

16-bit unsigned integer type

data Word32

32-bit unsigned integer type